Ocrelizumab Commentary: A New MS Drug With Breakthrough Potential And A Complicated History.

(What follows is my analysis of the potential promises and pitfalls associated with the experimental MS drug ocrelizumab. For those who have not already done so, I urge you to read – or at least scan – the interview I conducted with Dr. Peter Chin, one of the pioneering researchers who worked on this drug. Dr. Chin is the Group Medical Director of Neuroscience at the pharmaceutical company that makes ocrelizumab, Genentech – click here for the interview)

Ocrelizumab, a new MS drug scheduled for review by the FDA on March 28, 2017, has garnered breathless headlines in both the mainstream and medical press as a breakthrough medicine which has the potential to change the MS treatment landscape. Particularly heralded is the drug’s success in clinical studies in treating Primary Progressive Multiple Sclerosis (PPMS), a pernicious subtype of MS that currently has no approved therapies.

Assessing the overall potential of ocrelizumab is more difficult than with most new drugs, as the therapy has a complicated history that must be considered when synthesizing informed views about it. Ocrelizumab, which will be marketed under the brand name Ocrevus, is a close sibling of the much older drug Rituxan (rituximab), whose mechanism of action ocrelizumab closely mirrors. Rituximab, which is manufactured by the same company that makes ocrelizumab, is already being used in many parts of the world as an effective MS therapy, even though it was never officially approved for this purpose. The reasons why ocrelizumab rather than rituximab was advanced in studies as an MS therapy are somewhat controversial; complicating matters further are ocrelizumab’s failure in trials for use in treating other autoimmune diseases (lupus and rheumatoid arthritis). Therefore, when attempting to make a sober assessment of ocrelizumab, one must look not only at the drug itself, but also at how it currently came to be on the verge of FDA approval.

First, let’s look at ocrelizumab itself, in terms of how the drug works and what recent clinical trials reveal about its effectiveness in the treatment of both relapsing and primary progressive multiple sclerosis.

Ocrelizumab is the first B cell therapy for MS proven to be effective in late stage clinical trials. In very simplistic terms, the human immune system is comprised chiefly of 2 types of cells, T cells and B cells, which each use different mechanisms to attack and kill invading bacteria or viruses. Until very recently, the vast majority of MS researchers, who see MS as an autoimmune disease in which the immune system turns against the body’s own cells, considered the multiple sclerosis disease process to be driven almost exclusively by T cells. MS drugs such as Tysabri and Gilenya were designed to specifically target these cells. B cells were given short shrift, and were largely dismissed as having no real relevance in the MS disease process.

The success of ocrelizumab – a drug which destroys B cells – in treating MS has upended these prior assumptions and has forced researchers to rethink their multiple sclerosis disease models. In clinical trials, ocrelizumab, an intravenous drug administered approximately every 6 months, proved to be remarkably effective in treating relapsing multiple sclerosis, and even had a modest effect on PPMS. Let’s look at the actual trial results.

Two separate trials were conducted testing ocrelizumab against the interferon drug Rebif in patients with relapsing multiple sclerosis. These two trials were called OPERA 1 and OPERA 2 (click here). Both two-year trials involved one group of patients taking ocrelizumab and another taking the interferon drug Rebif, and comparisons were made as to the overall effectiveness of ocrelizumab versus the interferon drug. The results were very impressive. Compared to the Rebif treated patients, the ocrelizumab trial subjects experienced a reduction in relapse rates of 46% and 47% in the two trials. Additionally, there was a 40% reduction in confirmed disability progression and a 95% reduction in new enhancing lesions. These results rival or surpass any of the other MS drugs currently on the market. There were no significant differences in the number of adverse events (bad side effects) between the ocrelizumab and Rebif treated patient populations in the relapsing multiple sclerosis trials.

The ocrelizumab PPMS trial was named ORATORIO (click here). This trial lasted 2 ½ years, and randomly assigned 732 patients in a 2 to 1 ratio to receive either ocrelizumab or a placebo. In other words, twice as many trial subjects received ocrelizumab than received placebo. The highlight of this study was that the ocrelizumab treated patients experienced a 25% reduction in time to progression when compared to their placebo-controlled counterparts. Specifically, 29.6% of ocrelizumab treated patients and 35.7% of placebo treated patients experienced a measure of disability progression over the course of the study. This is the first time in a placebo-controlled scientific trial that any multiple sclerosis drug has displayed effectiveness in slowing down the progression of disability in Primary Progressive patients. Ocrelizumab also displayed efficacy over placebo in a number of other outcome measures as well, including the timed 25 foot walk.

As I discussed with Dr. Chin during our interview, it’s important to understand that ocrelizumab did not reverse or even stop the progression of disability in trial subjects. It slowed progression by about 25%. What does this mean for patients in a real-world setting? Well, speaking strictly in a broadly hypothetical basis, if an individual PPMS patient left untreated might need a cane four years after diagnosis, that same patient, if responsive to ocrelizumab, might not need a cane for five years. Again, this is strictly a hypothetical case; PPMS effects patients in widely varying degrees of severity. Additionally, the ORATORIO trial only lasted 2 and half years. How the drug's effectiveness manifests over longer periods of time is not yet understood.

Unlike the relapsing multiple sclerosis ocrelizumab trials, the PPMS trial did reveal some potentially troubling adverse events. Opportunistic infections (mostly respiratory infections and oral herpes) were more common in ocrelizumab than placebo, and the rate of cancer in ocrelizumab treated patients was approximately 3 times that found in placebo treated patients, 2.3% versus 0.8%. Though Genentech says that no direct causal relationship between the cancers in ocrelizumab treated patients could be established, the fact that slightly more than 1 in 50 trial subjects on the drug developed cancer is sure to raise eyebrows, but since similar cancer rates were not seen in the relapsing multiple sclerosis trials these numbers are surely open to question.

There are also some concerns regarding the design ORATORIO study. Back in the mid-2000’s, Genentech conducted a PPMS trial using rituximab, which at first was deemed a failure. Later review of the trial data revealed, though, that a subset of PPMS patients did appear to gain benefit from rituximab therapy (click here). These patients were generally younger than 50 years old, were less disabled, and had enhancing lesions on their MRIs. It’s generally thought that patients fitting this description account for between 10%-15% of the overall PPMS population. The ocrelizumab PPMS trial, though, included about 26% of patients fitting this profile, or approximately double that seen among real-life PPMSer’s. This means that the ORATORIO trial was heavily weighted with patients who were likely to respond to ocrelizumab, since the drug acts in much the same way as rituximab. The ocrelizumab PPMS trial was not designed to discern differences in the effectiveness of the drug between patients with enhancing lesions and those without, but Genentech says there was a “directional consistency” to the trial results, suggesting that the drug was effective in all patient subgroups to one degree or another. Still, the fact that the trial was frontloaded with likely responders is another eyebrow raiser, and may be something that the FDA looks at when making its approval decisions.

Okay, now that we’ve looked at the ocrelizumab MS trials themselves, let’s dive into the history of the drug. Back in the early 2000’s, some MS researchers began investigating whether therapies that destroy B cells might be effective in treating MS. As mentioned earlier, at the time this with a rather radical idea. The drug that was chosen for study was Rituxan (whose generic name is rituximab – click here), a drug developed by Genentech years earlier that had been approved in 1997 for use in fighting non-Hodgkin’s lymphoma and certain types of leukemia. Rituximab, like ocrelizumab, works by zeroing in on a protein found on most types of B cells, called CD20, and then killing the cells on which this protein is located. Though both drugs target and kill B cells, they do so in slightly different ways, and these differences may result in variances in safety and efficacy. Think of the drugs as two hitmen; one likes to slit his victims throats, the other prefers to strangle them. Both get the job done, but their differing killing techniques might effect witnesses differently. In the case of ocrelizumab and rituximab, these differences may effect the actions of other immune cells, thus accounting for possible differences in the safety and efficacy of the drugs.

In the mid-2000’s, MS researchers put rituximab to the test by using it in “proof of concept” trials in patients with RRMS and PPMS. When the trial results were revealed in 2008, the drug proved itself to be extremely effective in treating relapsing remitting MS, but not effective in treating PPMS (click here and here). It’s important to note that the RRMS trials were small, early stage trials, but the PPMS trial was larger and later stage. As mentioned earlier, later parsing of the PPMS data did reveal a subgroup of patients on whom the drug appeared to have some positive effect.

Given the success of the rituximab RRMS trials, the fact that a subset of the PPMS trial population appeared to benefit from the drug, and rituximab’s long history as a successful oncology drug, it’s reasonable to assume that the drug would have been greenlighted for further development as an MS treatment. Instead, all development of rituximab as an MS treatment was halted, and the focus shifted instead to ocrelizumab, a new experimental Genentech product that also targeted B cells via the CD20 protein. While there is some perfectly valid scientific rationale for this choice, many facts and circumstances point to financial motivations playing an oversized role in the decision to advance ocrelizumab rather than rituximab as a potential treatment for MS.

The scientific rationale for choosing to proceed with ocrelizumab is that the drug is comprised primarily of human proteins (the drug is a “humanized” monoclonal antibody), while rituximab contains a mix of mouse and human proteins (making it a “chimeric” monoclonal antibody, meaning that it contains proteins from more than one species). Theoretically, a humanized molecule should be better tolerated by patients than a chimeric drug, especially when used for treating chronic diseases which require continued administrations of the drug. That said, rituximab did have a very good safety profile in its role as an oncology drug, and very few adverse effects were seen in the early rituximab MS trials.

Genentech’s financial motivations for switching from rituximab to ocrelizumab were many. First and foremost was the fact that rituximab was due to come off patent in 2015, meaning that other drugmakers would be free to come in and market their own versions of the drug at that time. As ocrelizumab is a brand-new product, Genentech will have exclusive rights on it for decades to come. In addition, several corporate partnerships were also at play which made ocrelizumab the preferred candidate for further development. Here’s an explanation of the situation, from an article that appeared on the biotech industry news site Genetic Engineering and Biotechnology News in 2010 (click here). Keep in mind that Roche is the parent company of Genentech:

“The operating profits for Rituxan are currently split 60–40 between Roche and Biogen Idec, respectively. But profits for Ocrelizumab would be split 70–30 in Genentech's favor, accounting for Genentech’s enthusiasm to move ahead with the development of Ocrelizumab in MS, at the expense of Rituxan, which loses patent protection in 2015.”

Of course, there is no direct proof that the switch from Rituxan to ocrelizumab was driven primarily by financial considerations (except, perhaps, in files tucked away in the executive offices at Genentech), but I’ve learned through my years researching and writing about these topics that one can never be too jaded in assessing the motivations of the upper echelon decision-makers of Big Pharma. These are publicly traded companies whose officers are, by law, mandated to be beholden to their shareholders, not to the patients taking their products. Welcome to the realities of the medical industrial complex, in which diseases have been transformed into multibillion-dollar a year industries.

Whatever the circumstances, plans for further studies into the use of rituximab in treating MS were abandoned, and early trials using ocrelizumab to treat MS were initiated. In addition to the MS trials, ocrelizumab trials were also started on patients with rheumatoid arthritis (RA) and lupus erythematosus (LE). It’s interesting to note that rituximab was approved for use in treating rheumatoid arthritis in 2007, and has been used effectively and safely in that role since then (click here).

Genentech’s grand plans for ocrelizumab were almost completely disrupted in 2010, when the trials in RA and lupus were halted due to patient deaths and the occurrence of opportunistic infections (click here ). In the parlance of medical research, the risk versus benefit analysis in these trials did not warrant further study. In the parlance of everyday people, dead patients suck. It should be noted that patients in the ocrelizumab rheumatoid arthritis trial were also taking other immunosuppressive drugs, but then again so are most of the patients who have been using rituximab to treat their RA since its approval in 2007.

Ocrelizumab studies in MS were continued because these disastrous infections and patient deaths were not seen in early ocrelizumab MS trials, and also because it’s generally assumed that MS patients and their doctors have a higher tolerance for risk due to the potentially catastrophic nature of the disease (click here). This assumption is borne out by the MS community’s acceptance of drugs like Tysabri, which has a proven link to the deadly brain infection PML. Hundreds of MS patients have contracted this infection due to their taking Tysabri. Other MS drugs, such as Gilenya and Tecfidera, have also been linked to opportunistic infections such as PML. MS certainly isn’t a disease for the faint of heart.

In the years since the rituximab MS studies were shelved by Genentech, MS neurologists have been using the drug on an “off label” basis due to the obvious potential of the drug displayed in those early trials. “Off label” refers to the fact that doctors are free to prescribe any FDA approved drug for any indication whatsoever, even if the drug has not been approved for that purpose (click here). Many MS neurologists here in the USA as well as in Europe have been using rituximab to treat MS patients safely and effectively for years. The use of rituximab in MS is especially prevalent in Sweden, and a recent study out of that country that took a retrospective look at MS patients treated with rituximab found that the drug was startlingly effective and had an excellent safety profile (click here). As noted earlier, rituximab has also proven safe and effective in treating rheumatoid arthritis. Remember, the RA trials for ocrelizumab had to be halted due to opportunistic infections and patient deaths.

It should be noted that over its 20-year history rituximab has been linked to some cases of PML, but to a far lesser degree than drugs like Tysabri. In rheumatoid arthritis patients, it appears the rate of PML in Rituxan treated patients is on the order of 1 in 25,000 (click here). Rituximab has also been linked to other opportunistic infections, but again, at a lower rate than is seen in most other MS drugs. Let’s face it, any drug that profoundly changes the highly evolved human immune system is bound to open patients up to infections they wouldn’t otherwise contract. Ocrelizumab and rituximab both destroy B cells, one of the major components of the human immune system. No one knows what the long-term effects of living without any B cells might be. We do know, though, that the long-term effects of living with MS can be harrowing. Such is the state of the current MS treatment paradigm.

In conclusion, while the excitement generated by the impending approval of ocrelizumab for relapsing multiple sclerosis and primary progressive multiple sclerosis is certainly warranted, expectations, especially for those with PPMS, should be kept realistic. Ocrelizumab will likely slow the rate of disability progression for some progressive MS patients, and even though this isn’t the revolutionary change patients battling PPMS are so fervently hoping for, it is a start. Relapsing multiple sclerosis patients can expect ocrelizumab to be among the most effective disease modifying drugs on the market.

The fact that rituximab, a very similar drug with a proven record of efficacy and safety, is an available and very viable option should play into treatment decisions, as should the failed ocrelizumab trials in RA and lupus, and the increased cancer rates seen in the ocrelizumab PPMS trials (again, these rates could be aberrations). These factors need not make patients shy away from ocrelizumab, but there is every reason to explore them with your neurologist. Don’t be afraid to ask your doctor why they might favor one drug over another. This holds true when deciding on any MS treatment. Remember, the doctor-patient relationship should never be a dictatorship, but a partnership. Here’s to hoping that ocrelizumab proves itself worthy of the buzz it’s generated in advance of its anticipated FDA approval.

And here’s to more desperate hoping that MS researchers soon come up with methods other than profoundly kneecapping the human immune system in their search for ways to treat MS.

Ocrelizumab PPMS Trial Data Released, Offers Reasons for Hope and Concern

Last month, at the annual ACTRIMS (American Committee for Treatment and Research in Multiple Sclerosis) conference, the full trial results for the Ocrelizumab PPMS drug trial were finally revealed. These results had been much anticipated by the MS community, as there are currently no proven effective treatments for Primary Progressive Multiple Sclerosis, and many previous PPMS drug trials have ended in failure.

Coincidentally, a few days before the conference, Ocrelizumab received “fast-track status” by the FDA (click here). The “Fast-Track” designation is given to drugs which promise to fill a prior unmet need, and generally shortens the approval process from 10 to 6 months. Since PPMS has no approved treatments, Ocrelizumab fits the requirements for the designation. Though fast-track designation means that Ocrelizumab will have an expedited approval process, it does not guarantee that the drug will ultimately be approved.

The anticipation over Ocrelizumab, which was developed by Roche Pharmaceuticals subsidiary Genentech, stems from the fact that trial results appear to demonstrate the drug to be effective in slowing down progression of disability in PPMS patients. In results presented at ACTRIMS, Ocrelizumab showed itself to be very potent in treating RRMS (click here), and in PPMS the drug slowed down disability progression by 24% (click here), making it the first major pharmaceutical product to demonstrate effectiveness in treating Primary Progressive Multiple Sclerosis in a scientifically rigorous placebo-controlled trial.

The data set presented at ACTRIMS confirmed info originally released last year, but the numbers revealed at the recent conference provided more details on the patient population included in the study (click here). Specifically, results were provided for two different subsets of patients – those with enhancing lesions (which signify acute immune activity within the central nervous system) and those without enhancing lesions. Only about 15% of patients with PPMS display enhancing lesions on their MRIs, and it was widely assumed that Ocrelizumab would likely only be effective in treating those patients. The results provided by Genentech at ACTRIMS , however, demonstrated that the drug appears to be just as effective in patients whose MRIs did not show any signs of enhancing lesions.

Great news, right? Well, if the numbers hold up it is great news, but there are certain aspects of the Ocrelizumab PPMS trials that raise some red flags. Ocrelizumab is a close cousin of the decades old drug Rituxan, which is also manufactured by Genentech. Both drugs work in almost the exact same fashion, by targeting and destroying immune system B cells, effectively ridding the body of the cells for periods of at least six or seven months. Ocrelizumab, like Rituxan, is administered approximately every six months, in two intravenous doses given one or two weeks apart.

Rituxan was originally intended for use against blood cancers, but was later found to be effective in treating a variety of autoimmune diseases, including Lupus, Rheumatoid Arthritis, and Relapsing Remitting Multiple Sclerosis. The human immune system consists of a wide variety of cells, but is primarily made up of B cells and T cells. Therefore, Ocrelizumab and Rituxan both eliminate a major component of the very complex immune system, which, it’s assumed, is why they are effective in treating so-called autoimmune diseases. Though Rituxan was never officially approved for use in MS, many MS neurologists prescribe the drug “off label” for their RRMS patients, in whom it has proven to be very effective in reducing relapses and the occurrence of MS lesions.

Back in 2008, trials of Rituxan on PPMS patients were deemed a failure, much to the intense disappointment of many patients, myself included. Subsequent analysis of the data generated by that failed trial, however, revealed that a subset of patients did seem to have a somewhat positive response to Rituxan – namely younger patients who displayed enhancing lesions, had been more recently diagnosed, and were less disabled than other trial participants (click here). Instead of pursuing more targeted trials with Rituxan, though, the drug’s manufacturer, Genentech, decided to develop a newer version of the compound, and thus Ocrelizumab was born.

Why invent a new version of an older, proven drug that uses the exact same mechanism of action as that older drug? Well, Genentech says it was done to develop a safer, more effective product, but a cynical person might point out that Rituxan had already proven itself to be relatively safe and quite effective but was due to come off patent in 2015, meaning that its window for generating tremendous profits was rapidly closing. By the time new trials were completed, Rituxan would no longer have patent protection. A new version of the drug, on the other hand, could be a golden egg laying goose. But, of course, only a very cynical person would point that out, not someone is bright eyed and bushy tailed as me.

Anyway, back to the current Ocrelizumab PPMS trials. Based on the lessons learned from the failed Rituxan trials, it looks like Genentech populated the Ocrelizumab PPMS trials with patients who were selected specifically because they were more likely to respond to treatment (click here). Whereas only about 15% of PPMS patients display enhancing lesions on their MRIs, the Ocrelizumab trial included about 27% of such patients. When compared to the trial’s placebo group, the patients that received the actual drug had twice as many enhancing lesions, meaning their disease was much more immunologically active. In addition, compared to other PPMS trials (all failed), patients in the Ocrelizumab trial were generally more recently diagnosed, and were much less likely to have been on any prior disease modifying medications (in the parlance of the medical research community, most of the patients were “treatment naïve”).

Still, when the numbers were broken down at ACTRIMS, they showed that the drug decreased the rate of disability progression by about 24% in both patients with enhancing lesions and without enhancing lesions. However, each subset of patients was too small to make these results statistically significant, meaning that the trial was, in the parlance of the medical research community, “underpowered”. Knowing that this was sure to be a very important issue, why would Genentech go ahead with a trial that was underpowered in this regard? Wouldn’t logic dictate that they design the trial to settle this vital issue in a statistically definitive manner? Seems kind of strange, no?

What may ultimately turn out to be the most troubling aspect of the Ocrelizumab PPMS trial, however, is that 11 cancers were detected in patients taking Ocrelizumab, versus only two in the placebo group. Eight of the cancers in the Ocrelizumab patients were breast cancers, versus zero in the placebo group. This is especially concerning because back in 2010, when Ocrelizumab was first developed, trials were started not only in MS but also on lupus and rheumatoid arthritis patients. Both the lupus and rheumatoid arthritis trials were halted because of patient deaths (due mostly to opportunistic infections), but the MS trials were allowed to continue because it was thought that MS patients would have a higher tolerance for risk (click here). Interestingly, in the Ocrelizumab RRMS trials, which actually included more patients than the PPMS trials, “only” four cancers were detected in the drug group, versus two in the placebo group.

Incidentally, in its over two decades of service, Rituxan has not been associated with the development of cancers or an alarming number of opportunistic infections, although rare instances of PML (the brain infection that is so concerning in patients taking Tysabri) have been seen in patients taking the drug.

If anything derails an FDA approval for Ocrelizumab in treating PPMS it may very well turn out to be the cancer issue. Even though the positive effect on PPMS generated by Ocrelizumab isn’t overwhelming (a 24% decrease in progression rates is nothing to sneeze at, but then again it’s hardly the dramatic effect PPMS patients are desperately seeking), on its own it would seem encouraging enough to garner an approval. However, given some of the questions regarding trial design and safety issues, it will be very interesting to see what the FDA decides. Another one time promising MS drug, Cladribine, was rejected by the FDA primarily because of cancers detected during drug trials (click here).

For some expert opinions on Ocrelizumab, here are two videos. The first is a video of Ottawa MS neurologist Dr. Mark Freedman discussing progressive MS in general, and then commenting specifically on the Ocrelizumab PPMS trial results. For those of you with short attention spans, he starts talking about Ocrelizumab at the 3:50 mark of the video. Dr. Freedman has some very interesting comments regarding the drug and its effectiveness, and B cell therapy in general. The video is well worth watching.





Here’s another MS neurologist, Dr. Clyde Markowitz, Director of the MS Center at the University of Pennsylvania, who seems much more enthusiastic about Ocrelizumab and its prospects for treating PPMS:





Being the always curious person that I am, and also hyperaware that drug companies often funnel money to doctors who prescribe their products, I did some quick checking and found that Dr. Markowitz received $64,461 from various pharmaceutical companies between August 2013 to December 2014, mostly for “consulting” and “honoraria” fees (click here). At least $6000 of this rather large sum came from Genentech, which, it turns out, was the number one drug company in handing out payments to doctors during that period (click here). And this was before the Ocrelizumab trials were completed.

One can only imagine that Genentech is now going all out to, um, “influence” key doctors in its efforts to get the drug approved, much like politicians target key precincts and states in their quest to get elected. I’ve done plenty of ranting on the subject of drug companies making direct payments to the doctors who prescribe their products in previous blog posts, so I’ll refrain from launching into yet another insane tirade here, but suffice it to say I’ve yet to find any logical argument as to why this practice is tolerated, much less legal.

In all fairness, since Dr. Freedman practices in Canada, I was not able to find any info on payments he might’ve taken from drug companies. The truth is that very few MS neurologists are not on the pharmaceutical company dole. I’d encourage you to enter your doctor’s name in the “Dollars for Docs” database (click here), and see if your neuro has his hand in the cookie jar. Again, this doesn’t mean that the doctors named in the database allow pharmaceutical company money to affect their decision making process, but then again, the pharmaceutical companies wouldn’t be doling out millions and millions of dollars if they weren’t getting an appreciable return on investment.

Okay, sorry, I got a little sidetracked there. I certainly hope that all of my concerns about Ocrelizumab turn out to be completely unfounded, as having even a modestly effective treatment readily available for PPMS would be a major step forward in fighting the disease. However, it seems clear (to me, at least) that going after the immune system isn’t going to be the magic bullet that solves the Progressive Multiple Sclerosis problem, or the broader overall Multiple Sclerosis riddle.. Researchers urgently need to step outside the box and start coming at the issue from new angles if any truly dramatic progress is ever going to be made. In the meantime, here’s to hoping that Ocrelizumab proves itself to be a safe and reliable option for Primary Progressive patients, whose desperation for proven treatment options is beyond words.

Experimental MS Drug Ocrelizumab Deemed A Success In Progressive MS Trial, But Questions Remain

Last week, the drug company Genentech (a subsidiary of Swiss drugmaker Roche Pharmaceuticals) announced that its Phase III trials for treating Primary Progressive Multiple Sclerosis with the experimental MS drug Ocrelizumab had met with success. According to a press release titled “Roche’s Ocrelizumab First Investigational Medicine to Show Efficacy in People with Primary Progressive Multiple Sclerosis in Large Phase III Study”, the drug met the trial’s primary endpoint, “showing treatment with Ocrelizumab significantly reduced the progression of clinical disability sustained for at least 12 weeks compared with placebo, as measured by the Expanded Disability Status Scale” (click here). Earlier this summer two previous trials had shown Ocrelizumab to be more effective than the beta interferon drug Rebif for treating RRMS, resulting in reduced relapse rates, number of MS lesions, and a reduction in progression of disability (click here). Ocrelizumab is an intravenous drug that is administered twice over a two-week period, and then not again for six months.

While this would all appear to be great news, especially for people with PPMS who currently have no approved treatment options, just how great this news actually is remains to be seen as the press release provided absolutely no details on the study results, which will only be revealed on October 9 and 10^th at the annual European MS conference ECTRIMS, being held in Barcelona, Spain. Understandably, news of Ocrelizumab’s success in treating PPMS has created quite a buzz in the MS community as well as in the financial pages of publications around the world, as the drug stands a good chance of becoming the latest multibillion-dollar blockbuster MS treatment (click here).

There is reason to believe, however, that Ocrelizumab may only be effective in treating a subset of patients suffering from Primary Progressive MS, specifically those who are less disabled (still walking), younger, and who display enhancing lesions on their MRIs. And though the press release states that the side effects experienced by study subjects taking Ocrelizumab were not much different than those who were given a placebo, back in 2010 trials testing Ocrelizumab for the treatment of Lupus and Rheumatoid Arthritis had to be abandoned because of an unacceptable number of serious and sometimes fatal opportunistic infections seen in trial subjects (click here).

How can I make any assumptions on Ocrelizumab’s efficacy at all based on the scant details divulged in Roche’s press release, you may ask? Well, it turns out that Ocrelizumab’s mechanism of action is nearly identical to that of a much older drug also manufactured by Roche, called Rituxan (Rituximab), which has been used for decades to treat cancers of the blood and for the last seven or eight years, on an off label basis, to successfully treat Relapsing Remitting Multiple Sclerosis.

In fact, back in 2008 Rituxan completed early stage trials (phase I and phase II) investigating its use in treating both RRMS and PPMS. In these earlier trials, Rituxan was deemed successful in treating RRMS (click here), but the drug failed in its much-anticipated trial for PPMS (click here). Subsequent to the PPMS trial’s completion, however, researchers combing through the data discovered that Rituxan did appear to have a beneficial effect on a subset PPMS patients, specifically those who were less disabled, were 50 years old or younger, and who had enhancing lesions, (click here). Ocrelizumab’s mechanism of action is so nearly identical to Rituxan’s that within the industry the drug has been nicknamed “brother of Rituxan”.

Why then was Rituxan not further investigated for the treatment of RRMS and PPMS, Roche and Genentech instead shifting their all of their attentions to costly process of developing a brand new drug that works in a very similar fashion, Ocrelizumab? Well, this is where things get interesting and more than a little bit curious. If I were a cynical man I might conclude that purely financial considerations were involved, but far be it for me to be so cynical. Instead, I’ll present you with the evidence as I know it, from which you may draw whatever conclusions you wish.

As I mentioned earlier, Rituxan is an older drug, and it is scheduled to lose its patent protection this year. Once the Rituxan comes off patent, Roche will lose its exclusive rights to the drug and thus the ability to generate tremendous profits from marketing it (click here). This fact made the return on investment of proceeding with very costly late stage MS trials in 2008 decidedly negative even if they proved wildly successful, because after 2015 another company could step in and market a generic version of Rituxan, thereby killing the drug’s profit making potential for Roche.

Both Rituxan and Ocrelizumab are in a class of drug called monoclonal antibodies, which are manufactured antibody cells that work by targeting specific cells in the human body. Rituxan and Ocrelizumab work by attacking B cells, one of the two primary types of cells that comprise the human immune system (these two types of cells are called T cells and B cells). They both seek out the same protein expressed on the cell walls of B cells, CD 20, and both drugs ultimately destroy almost all of the B cells in the human body using nearly identical mechanisms.

This anti-B cell approach is not taken by any other current MS drug, as until very recently it was believed that the MS disease process was driven primarily by T cells, which are the focus of drugs such as Tysabri and Gilenya (the latter of which recently failed in a recent PPMS trial). The fact that Rituxan and Ocrelizumab – which exclusively target B cells – are proving to be so effective in battling MS is forcing researchers to completely rethink much of what has been assumed in the understanding of the disease. Roche’s recent Ocrelizumab press release also contains hints that the drug’s action on B cells may have some neuroprotective properties, which if true would be truly remarkable. Of course, since Rituxan has already been used successfully to treat RRMS for quite a few years, the knowledge that a B cell immunosuppressant was capable of dramatically impacting the Multiple Sclerosis disease state was readily available, but also easy to ignore given the somewhat rogue nature of treating MS with Rituxan.

The difference between Ocrelizumab and Rituxan is the fashion in which they are manufactured. All monoclonal antibodies are “biologic” drugs, meaning they are derived from living animal cells, usually from a combination of mouse and human tissues. Most older monoclonal antibody drugs, such as Rituxan, are what is known as “chimeric monoclonal antibodies” (click here), meaning they contain both mouse and human DNA. Newer drugs such as Ocrelizumab are “humanized monoclonal antibodies” (click here), and have their DNA structure manipulated to more fully resemble completely human cells.

Although one might assume that humanized monoclonal antibodies would always be preferable to those that contain non-human DNA, Rituxan has been used for decades and has shown itself to be a very safe and effective drug. Although some cases of opportunistic infections, including PML, have been associated with Rituxan, they’ve appeared far less frequently than those seen with Tysabri (click here). Rituxan has proven itself successful in treating RRMS both in trials and in real life practice (the drug is FDA approved for the treatment of Rheumatoid Arthritis, and is used off label to treat a variety of other autoimmune diseases).

The Rituxan PPMS trials, though at first deemed a failure, did reveal a subset of PPMS patients on whom there was evidence of efficacy, and it appears that the Ocrelizumab PPMS trial was designed to capture as many of this type of patient as possible (click here). Had Roche pushed ahead with its Rituxan MS trials even in the face of a looming patent expiration we might have had another very effective treatment for RRMS, and perhaps even PPMS, for at least the last five years. Alas, ‘twas not to be, quite likely because Rituxan was scheduled to soon lose its patent protection.

I truly hope that when the full details of the Ocrelizumab trials are revealed at the upcoming European MS conference they exceed all expectations and make Rituxan look like a rusty old Model T compared to Ocrelizumab’s shiny brand new Maserati. If the new drug is in fact capable of stabilizing the disease progression of the majority of PPMS patients we will have a true game changer on our hands. Even if, as I suspect, the drug is shown to be effective on just a subset of PPMS patients – those who are younger, less disabled, and have enhancing lesions – it will represent a tremendous leap forward in the treatment of what has up until now been an untreatable disease. The fact that the drug exclusively targets B cells and benefits both the relapsing remitting and progressive forms of Multiple Sclerosis should send researchers scrambling to develop an entirely new model of the MS disease process, and, who knows, may lead to an eventual understanding of the ever elusive underlying cause of Multiple Sclerosis.

Here’s to hoping that the new drug proves to be as safe and reliable as the old one, Rituxan, and Ocrelizumab will become not only a powerful new weapon in the fight against MS, but also a catalyst for an entirely new way of thinking about the disease. For people with PPMS, this successful drug trial, even if limited, finally opens a door to treatment options and allows rays of hope to filter in through the clouds. We’ll begin to get our answers in just about a week, and I for one can’t wait for the data to be released.

Geez, that last line may be just about the wonkiest sentence I’ve ever written. I guess I just have to own up to the fact that I’m now a full-fledged MS research nerd…

Ocrelizumab Update – RRMS Trials Successful; PPMS Trial Shows Positive Effect, But Many Questions Left Unanswered

When I last posted to Wheelchair Kamikaze, I profiled the experimental MS drug Ocrelizumab, which was developed by Swiss drug giant Roche (and their US subsidiary Genentech). In press releases put out by the company two weeks ago (click here), Ocrelizumab was touted as the first MS drug shown capable of putting the brakes on Primary Progressive Multiple Sclerosis (PPMS) – a subtype of the disease which until now has been largely untreatable – as well as it being highly effective in treating the more common Relapsing Remitting Multiple Sclerosis (RRMS). These results were even more noteworthy because Ocrelizumab is the first MS drug to specifically target immune system B cells, while other currently available MS drugs (Tysabri, Gilenya) were developed to target T cells, which until now were believed by many to be the primary culprits driving the MS disease process.

Though the initial Ocrelizumab press releases were scant on details, the news certainly appeared promising, though reservations were expressed by many MS researchers based on Ocrelizumab’s development history and its close similarity with another Roche product, Rituxan, a much older drug that had gone through early trials in RRMS (very successful) and PPMS (largely a failure, but with some hints of success) back in 2005-2008. Rituxan’s development as an MS treatment was halted by Roche because of what many believe to be strictly financial concerns. Reading my previous essay (click here) will provide much background on Ocrelizumab’s development and the issues surrounding the drug.

Roche presented the details of the Ocrelizumab RRMS and PPMS trials this past weekend at the ECTRIMS conference in Barcelona, Spain. The RRMS trials were named OPERA I and OPERA II, and the PPMS trial was named ORATORIO. The results of the OPERA I and OPERA II RRMS studies were indeed impressive. These studies compared Ocrelizumab to Rebif, an interferon drug long used to treat RRMS, and found that treatment with Ocrelizumab resulted in a 50% reduction of annualized relapse rates, a 40% reduction in progression, and an 80% reduction in enhancing lesions as shown on MRI when compared to patients taking Rebif (click here – login required, but sign-up process is easy and well worth it). Adverse events were found to be similar in both groups, which is encouraging as Rebif is considered one of the safer MS medications currently available.

It should be noted, however, that the two-year length of these trials may be insufficient to detect longer-term problems that may develop as a result of the intense B cell suppression that is Ocrelizumab’s primary mechanism of action. Nevertheless, it does appear that Ocrelizumab will become a very valuable weapon in the growing arsenal of drugs used to combat RRMS, though, like all current MS drugs, it doesn’t do a thing towards actually curing the disease. But I’ll save that rant for another day…

(Please note, the following information and accompanying commentary were largely gleaned from materials contained in articles and interviews that can be accessed by clicking here, here, here, and here. I would urge all to read them for greater context and background)

Results of the ORATORIO PPMS study, while initially impressive, still remain riddled with questions. Despite the screaming headlines hailing Ocrelizumab as a “revolutionary new MS drug” by the – as usual – hyperbolic mainstream medical media (click here), the actual picture remains far more nuanced. The ORATORIO trial design was heavily influenced by the results of the failed Rituxan PPMS trial back in 2008. Though that trial was officially deemed unsuccessful, subsequent examination of the data revealed that a subset of PPMS patients in the study were seemingly helped by the drug. These patients were generally younger, had shorter disease duration, were less disabled, and had enhancing lesions on their MRIs. It’s thought that patients who fall within these parameters make up about 15% of the overall PPMS population.

It appears that in designing the ORATORIO study, Roche chose trial subjects who were most likely to benefit from Ocrelizumab treatment, specifically those who fit the demographic and disease parameters outlined above. As presented at ECTRIMS, the results of the ORATORIO study are indeed impressive, demonstrating a marked slowing of disease progression, a reduction in MS enhancing lesions, a reduction in brain volume loss, and a stable time to walk 25 feet when compared to trial subjects given a placebo. Of course, these results also mean that many of the ORATORIO trial subjects were patients with enhancing lesions (only a fraction of PPMSer’s have such lesions) and who were relatively less disabled (as evidenced by the fact that they could still walk). The majority of trial subjects also appear to have been relatively recently diagnosed, with a disease duration of approximately 3-5 years, and were under 50 years old.

Unfortunately, when Roche presented the ORATORIO results at ECTRIMS, they declined to detail the breakdown of results by patient subgroups, claiming that such subgroup analysis had not yet been satisfactorily completed. This beggars belief, as one would think that examining the data in such a way as to determine which patient groups benefited the most from treatment would be among the highest research priorities, especially given the mixed results of the previous Rituxan PPMS trials. Instead, Roche chose to give a broad overview of favorable trial results without answering some of the most important questions about those results, primary among them whether or not the patients who most benefited were those with enhancing lesions. Indeed, in the Q&A period following Roche’s presentation, presenters were questioned on just this issue by conference attendees, who were given no suitable answers other than promises that the data would be forthcoming. Roche's presentation led several experts to say the primary progressive data were less impressive than those seen with Ocrelizumab in relapsing remitting disease.

Although Roche portrayed the safety profile of Ocrelizumab in the ORATORIO trial to be excellent, they did note that there were 11 cancers detected during the ORATORIO trial on patients taking Ocrelizumab, versus only two in the placebo group.

The results of the Ocrelizumab RRMS and PPMS studies have not yet been published in any scientific journals, and it is expected that much additional data will need to be provided to publishers before the trial results will be deemed fit for publication. Getting the drug through the regulatory approval process required by government agencies such as the FDA will also necessitate a much greater detailing of trial results, including subgroup analysis which will shed light on just which patient groups were treatment responders. While it seems that the RRMS results will likely stand up to more intense scrutiny, the PPMS results may prove to be less dramatic than originally portrayed when subjected to the spotlight of journal publication and regulatory approval.

That said, even in a worst-case scenario in which only a small subgroup of PPMS patients, those with enhancing lesions,  prove to benefit from Ocrelizumab treatment, the fact that any headway at all has been made in treating PPMS is a significant step forward. If in fact the drug’s efficacy is limited to patients with enhancing lesions, and such lesions are most likely to be found in patients in the earliest stages of the disease, the importance of early diagnosis will be brought to the forefront. Given current diagnostic tools and techniques, many patients with PPMS aren’t correctly diagnosed until the disease has long since taken hold, beyond the period when enhancing lesions are likely to be present. Additionally, the fact that Ocrelizumab targets B cells should open up new avenues of investigation for MS researchers worldwide, as this potential mechanism of MS disease action has until now been largely discounted by most mainstream researchers. Perhaps these investigations might finally unravel some of the deepest mysteries of the disease, and (crossing the fingers I can still cross) eventually lead to a cure for all forms of the disease.

At this point, only time will provide us with the answers we seek. The next chapters of the Ocrelizumab saga will be getting these studies peer-reviewed and published in medical journals, a process which will shed much light on issues still in need of clarification. Roche is targeting the first quarter of 2016 for regulatory approval in both RRMS and PPMS. It will be very interesting to see whether or not Ocrelizumab is approved for the PPMS population as a whole, or, as many researchers suspect, for only a subgroup of progressive MS patients. Again, even if the latter case holds true, we will have at least made some headway in the fight against an insidious form of Multiple Sclerosis that until now has defied efforts to combat it.

At long last, it appears that the attentions of Multiple Sclerosis researchers are finally focusing on progressive MS, an area of investigation which until very recently had largely been neglected. The confounding problems represented by progressive MS will never be solved until well-funded trials are directed specifically at this disease subtype, a circumstance that finally seems to be coming to fruition. And that’s no small thing…

Ocrevus Exclusive: Interview with Pioneering Researcher Dr. Peter Chin

Dr. Peter Chin

Late last month I was contacted via email by a representative for the pharmaceutical company Genentech, asking if I would like to interview one of the researchers who played an instrumental role in the development of the new MS disease modifying drug ocrelizumab. At first I assumed I must’ve received the email as the result of some sort of clerical error, what with my being a mere blogger and all, but I figured if they’re offering, I’m accepting.

Thus, I present the below interview with Dr. Peter Chin, the Group Medical Director of Neuroscience at Genentech. Dr. Chin has been involved with the development of ocrelizumab (tradename Ocrevus) for well over a decade, and was a pioneer in the study of the role of immune system B cells in multiple sclerosis. This line of thinking has upended much of what had previously been thought about the disease, as the working theory up until very recently was that immune system T cells were the primary culprits that should be targeted when developing drugs aimed at alleviating multiple sclerosis. Ocrelizumab is a very close cousin of rituximab, also known by its brand-name Rituxan, another Genentech product which many neuros have been using off label to treat their MS patients.

Ocrevus, an intravenous medication requiring infusions approximately every 6 months, has garnered a tremendous amount of attention of late, as it is the first drug ever to show efficacy in treating progressive MS in a late stage clinical trial and is in the process of being considered for approval for the treatment of PPMS (as well as relapsing multiple sclerosis) by the FDA. The drug has generated blaring headlines and hyperbolic chatter in the medical and mainstream press, and talking directly to Dr. Chin presented a valuable chance to cut through the clutter and get the pertinent info straight from the horse’s mouth. Not to insinuate that Dr. Chin is a horse; au contraire, he proved to be an extremely erudite gentleman during our extensive talk. He was also quite generous with his time, as our scheduled 30 minute interview lasted for nearly an hour.

The following interview is filled with a tremendous amount of important information. It’s been lightly edited for readability. I’ll publish it here without commentary and follow-up next week with my take on the potential promises and pitfalls of ocrelizumab, an intriguing new MS medication.

As you read through the interview, you’ll notice a brand-new feature on these pages called “WK notes”. These are explanations in everyday language of some of the more esoteric medical terminology that cropped up during the interview. And, if anybody’s wondering, “WK” stands for Wheelchair Kamikaze, not Wicked Kool.



WK: Dr. Chin, let me thank you for taking the time to do this interview. To start, could you explain the importance of the relatively recent research into the role of B cells in the Multiple Sclerosis disease process? I understand that when this research first started, it was not in the mainstream of general Multiple Sclerosis research.

Dr. Peter Chin: Genentech started collaborating with leading academic researchers at major universities to look into the possibility that B cells might be important in MS about 15 years ago. To some degree this was not the mainstream line of thinking, but there were researchers who had a scientific hypothesis and believed that B cells might be important because they are the cells that differentiate into cells that secrete antibodies, and antibodies are implicated in the disease pathogenesis (WK note: pathogenesis refers to the conditions that lead to the development of a disease). They are found in lesions and in the cerebral spinal fluid as oligoclonal bands (WK note: more commonly referred to as O-bands, these are one of the primary diagnostic indicators that neurologists look for when examining the spinal fluid of potential MS patients). So there was some rationale, and I think it was an exciting time when the first proof of concept studies unblinded, showing that B cells may play a more important role than anybody thought.

WK: Just to be clear, before this time it was assumed that this was a T cell mediated disease, is that right?

Dr. Chin: That’s correct. The vast majority of efforts in developing new medications up until that point were directed towards T cells.

WK: Genentech was the first to study the use of B cell therapies in MS with the drug Rituxan, whose generic name is rituximab, which was the precursor to ocrelizumab, which will be called Ocrevus if it gets FDA approval, correct?

Dr. Chin: Yes, that’s right. Genentech developed rituximab a long time ago for oncology, and we learned a lot about the medication from there. Rituximab provided a proof of concept that B cells might be important in MS, but we advanced another molecule that we believe has the best potential for long-term treatment from both the safety and efficacy standpoints for people living with MS, and that’s ocrelizumab. Ocrevus is a humanized molecule which is different from rituximab because rituximab is what we call a chimeric antibody, which has a portion of its protein sequence that is derived from mice. (WK note: a chimera is a mythical beast made up of the parts of different animals, such as a winged lion. Chimeric drugs are those that include the DNA of both humans and animals.) Ocrelizumab is a humanized molecule, meaning most of its protein sequence is human. That becomes important, particularly in a chronic disease, because ocrelizumab is hypothetically less likely to generate an immune response against the drug itself than a drug that includes more non-human DNA.

WK: Can you tell us a bit about the proof of concept studies that used rituximab to treat RRMS?

Dr. Chin: Yes, it’s important to recognize that these were small proof of concept studies, with a single dose of rituximab against placebo. It did show a reduction in MRI enhancing lesions, which was the primary endpoint, and also showed about a 50% reduction in relapses against placebo, in a six-month period. So it did provide some preliminary information that targeting CD20 positive B cells might be effective (WK note: CD20 is a protein that appears on the surface of a variety of different types of B cells). Around the same time, ocrelizumab was being studied in rheumatoid arthritis in a dose ranging study. One thing we looked at was multiple doses of ocrelizumab and their effects on B cells as well as efficacy and safety. We also looked at immunogenicity (WK note: immunogenicity is the ability of a substance to provoke a response in the immune system) and found that this was a molecule that had potential for chronic autoimmune conditions, and decided to advance ocrelizumab for Phase II development in RRMS, which led to the Phase III development program which was just published in the New England Journal of Medicine.

WK: PPMS trials were also done with rituximab about 10 years ago, too. Since I am suspected of having PPMS, I was tremendously interested in that particular trial. Can you talk a little bit about that trial?

Dr. Chin: The rituximab PPMS trial is a trial that I was involved in, actually, and it was a Phase II/III study of 439 patients comparing rituximab versus placebo. It was a single study, and it was a negative study. Meaning that the primary endpoint, which was the time to 12 week confirmed disability progression, was not significantly different than placebo.

WK: My understanding is that even though the trial as a whole was negative, when the data was looked at retrospectively there was a subset of patients – primarily those who were younger, less disabled, and had enhancing lesions – that did appear to gain benefit from the drug. Is that correct?

Dr. Chin: That’s right, although this finding was hypothesis generating rather than confirmatory, meaning it was not proven in the study.

WK: Okay, let’s talk about the Ocrevus MS trials, which are creating chatter all around the MS community. Starting with the RRMS studies, some of the results reported were pretty astounding. Could you describe those results?

Dr. Chin: The phase III RMS studies were called OPERA 1 and OPERA 2 (WK note: RMS refers to both RRMS and Relapsing SPMS). These were two, two-year trials – double-blind, double dummy studies – comparing ocrelizumab head-to-head to the interferon beta 1a drug Rebif. Here the relapse reductions were 46% and 47% compared to interferon. There was also a 40% reduction in confirmed disability progression, and approximately 95% reduction in gadolinium enhancing lesions compared to interferon. These are very promising results from an efficacy standpoint, and have the potential to really change the way that MS is treated.

WK: Yes, those are extremely impressive results. Were there any instances of PML, the potentially fatal brain infection that has been seen in patients taking some of the other MS disease modifying drugs, in any of the patients in the Ocrelizumab trials?

Dr. Chin: No cases of PML have been observed in any of the ocrelizumab development trials.

WK: Okay, let’s move onto the PPMS trial, which is really generating tons of buzz. Could you please summarize the studies and their findings?

Dr. Chin: The ORATORIO study is the Phase III double blinded study, lasting more than 2 and half years, comparing ocrelizumab to a true placebo. The primary result of this study indicated a 24% reduction in the risk of 12 week disability progression. Importantly, there was also a 25% reduction in the risk of 24 week disability progression, which is generally considered a more robust outcome measure for disability progression.

That 25% reduction is the reduction in risk over the entire timeframe for all the patients that were included in the trial, and that’s at least 120 weeks, but there were patients who entered the study early in the treatment period that were on the drug for a longer period of time. So the 25% reduction in the risk of disability progression is the figure for the entire cohort for the entire length of the trial.

WK: Okay, so the data from the trial tells us that this new drug for people with primary progressive MS is not reversing disability or stopping the progression of disability, but it is slowing the accrual of disability. Is that a fair assessment?

Dr. Chin: Yes, the primary result of the study is the 24% reduction in 12 week confirmed disability progression. So that is not a measure of improvement, and you’re correct, it shows a delay in the progression of disability as measured by EDSS (WK note: EDSS is a scale that measures the level of disability in MS patients).

WK: Realistically, then, PPMS patients on Ocrevus can expect that they probably will keep progressing, but it would be at a slower rate than if they were left untreated?

Dr. Chin: That’s a hard question to answer for any individual, but the overall results for the population of the study show a slowing of disability production as measured by EDSS, there is a slowing of the worsening of the timed 25 foot walk, which is another major end point in progressive MS trials. This is literally a measure of how long it takes to walk 25 foot feet. There is a slowing in the rate of brain volume loss, and, at least over the course of the trial, there appears to be a stabilization of the accumulation of T2 lesion accumulation. On this end point the placebo treated patients continue to accumulate T2 lesion volume and patients on ocrelizumab experienced a small decrease that was stable over the course of the two and half years or more.

WK: You previously noted that ocrelizumab was tested in trials for the treatment of rheumatoid arthritis. Weren’t those trials halted because of opportunistic infections and patient deaths?

Dr. Chin: There were opportunistic and serious infections observed in the Phase III program in rheumatoid arthritis. What’s important here is that rheumatoid arthritis is a different treatment paradigm. These are patients that are also on concurrent immunosuppressants in addition to ocrelizumab. (WK note: many of the rheumatoid arthritis patients in the ocrelizumab trial were taking other immune suppressing drugs in addition to ocrelizumab.)

WK: And ocrelizumab was also being trialed for treating lupus, and those trials also had to be halted for similar reasons, correct?

Dr. Chin: There were 2 studies in lupus. Ocrelizumab was studied in systemic lupus erythematosus (SLE), and that was discontinued primarily because the expectation for efficacy was low based on another study involving B cell targeting. The other study was on lupus nephritis, and there were serious infections that were observed, but the decision to halt was based on an assessment of potential benefits versus risks.

The same is true for the Rheumatoid Arthritis program. The potential for benefit/risk improvements over existing therapies, based on the data that were already on hand, was deemed not to be promising. So the studies were discontinued.

WK: Were any of these same problems – opportunistic infections and patient deaths – seen in either the RRMS or PPMS Ocrevus trials?

Dr. Chin: The ocrelizumab Phase III safety results for MS overall were very favorable. This is the data that was just published in the New England Journal of Medicine. The proportion of patients in the relapsing study with any adverse event were similar to those who were on beta interferon, and the proportion of patients with any serious adverse event, including serious infections, were also similar to interferons. The same is true with the primary progressive MS trial, which was a slightly longer trial. When compared to placebo the proportion of any adverse event, any serious adverse event, or any serious infection was comparable to placebo.

WK: In looking over the ORATORIO PPMS trial results, it appears that there were higher rates of cancer among the ocrelizumab treated population when compared to the placebo population. I believe the numbers were 2.3% of the ocrelizumab population developed cancers, while .8% of the placebo group developed cancers. Is that of any real concern?

Dr. Chin: There is a numerical imbalance in the number of cases observed, but the overall numbers are small. This is not a confirmed risk, but I will say that patient safety is important to us and we do continue to monitor this in ongoing clinical trials. We don’t believe that the totality of the data supports a causal relationship, but we will continue to monitor this in our ongoing Phase III open label extension studies. So far, in the additional data we’ve accumulated, there is no increase in the rate of cancers being seen.

WK: The earlier rituximab trials demonstrated that there was a subset of the PPMS population on which the drug appeared to be effective – primarily younger patients who were less disabled and had enhancing lesions. In the ocrelizumab PPMS study this group made up about 26% of the test subject population, whereas in the general PPMS population the number of patients displaying those characteristics is thought to be somewhere between 10%-15%. So it would appear that the ocrelizumab study was populated with a higher percentage of patients who might be high responders than are present in the real-life PPMS population. Can you comment on this possible disparity?

Dr. Chin: The first thing I would say is that the study results are designed to assess the efficacy in the entire study population. So this was not a study only of patients of a certain younger age or only of patients who had enhancing lesions or did not have enhancing lesions. I say that because when you look at subgroup results, it’s important to recognize that these studies are not designed to address the efficacy in the subgroups. Also, I would note, that in data that we presented earlier this year that there is a directional consistency, meaning that there is still a reduction in disease worsening in patients who both had enhancing lesions and did not have enhancing lesions at baseline. This was presented at the ACTRIMS meeting in February 2016.

WK: Are there differences between the mechanisms rituximab and ocrelizumab use to eradicate CD20 B cells?

Dr. Chin: There are differences in how they bind to CD20 molecules on the B cells. And there are differences in what we call effector function, and that’s the portion of the antibody that interacts with other elements of the immune system to remove the cells. So, yes, there are differences in the functions of the two molecules.

WK: The mechanism of ocrelizumab in PPMS patients that do have enhancing lesions – which indicate active inflammation within the central nervous system – would presumably be much the same as you would see in the RRMS model, in that the drug clearly reduces inflammation by targeting B cells. Can you propose a mechanism of action for ocrelizumab that would be beneficial for the vast majority patients with PPMS who don’t have signs of enhancing lesions or any other signs of active inflammation in their central nervous systems?

Dr. Chin: That’s a very challenging question, and a good question. I think what you’ve hit on is an area that the entire research community in MS is thinking about. It’s not a question that anyone can answer definitively at this point, because the mechanism of progressive MS and the evolution of progressive MS over time isn’t completely understood. I think there’s a recognition in the research community that the biology has become very complex and how intervening in one way will impact the disease is hard to predict. Genentech is a member of the Industry Forum of the International Progressive MS Alliance, a coalition of organizations that has formed to address the kinds of questions that you’re asking, so we contribute what we can to the understanding of progressive MS. But that’s a really big question that you’re asking.

I think our understanding of B cells currently, which I will acknowledge is ongoing and evolving, is that B cells do interact with T cells, and by removing B cells from circulation we may be breaking that interaction. We also know that B cells differentiate into plasma cells and plasmablasts which create antibodies, which might also be involved. (WK note: plasma cells and plasmablasts are among the more mature types of B cells circulating in the human body.) B cells also create a number of cytokines that also impact and potentially stimulate other parts of the immune system. (WK note: cytokines are chemicals secreted by cells that trigger actions in other cells.) There may be multiple ways that selectively targeting b-cells might be leading to efficacy.

WK: Just a couple of weeks ago we learned that the December 28, 2016 date for and FDA decision on the approval of ocrelizumab had been delayed until March 28, 2017. Can you shed some light on the reasons behind that postponement?

Dr. Chin: We did have an announcement about this extension of the date, and yes it’s March 28, 2017, which is the expected action date by the FDA. The FDA needs more time to review additional data that was submitted during the review, regarding the commercial manufacturing process. What I want to stress is that this is not related to the review of safety or efficacy data. It’s about the manufacturing process and the data regarding that process. This extension of the action date by the FDA is a commonly used procedural tool and they use it to allow more time to evaluate additional information. It’s not uncommon for questions that come up during the review, and as a result of those questions additional data get submitted. It’s just the nature of the process.

WK: As a final question, as a scientist who has devoted a large part of your career to studying MS and progressive MS, what do the trial results from the PPMS ocrelizumab studies indicate to you about the disease, and what can we look forward to in the future for what had previously been an untreatable and rather terrible malady?

Dr. Chin: I think the first thing I’d say is that the data that we just published in the New England Journal are really landmark data for a number of reasons. One, they highlight and confirm that B cells are important in MS, which is still a relatively new concept. That’s a major area of science that Genentech has contributed to that the entire community is continuing to work on. From a clinical trial results standpoint, this is the first molecule that has shown efficacy in both relapsing MS and primary progressive MS. It’s the first molecule under consideration for approval by the FDA for both RRMS and PPMS. It’s an exciting time and an exciting potential new medicine to be working on.

Particularly in regards to primary progressive MS, I want to make the note that Genentech is the only company that has actually done two Phase III studies on primary progressive MS. It’s something that we’ve been very committed to because of the unmet medical needs and the fact that there are no approved therapies. My great hope is that people will start to see that maybe we can do something about primary progressive MS, and build upon this first step with ocrelizumab, which is a very meaningful one.

WK: On behalf of all Wheelchair Kamikaze readers, I’d like to offer a tremendous thank you for doing this interview. On a more personal level, I’d like to thank you for devoting your career to unraveling the mystery of this dreadful disease. It’s tremendously important for a lot of people who suffer from all forms of MS, but especially those who have been without any proven treatment options for so long, who are stuck living with the misery that is progressive MS.

Dr. Chin: Thank you for that, Marc. I think it’s important for you to know that there are hundreds of people at Genentech and Roche who have worked on these primary progressive trials and the RMS trials for many years. I think I can speak for all of them that they do it with a passion for making a difference, understanding the degree of unmet need that’s out there.


I hope readers have found real value in the above interview. I’d love to hear your thoughts in the comments section.

As I stated earlier, I’ll follow this up next week with an essay on my thoughts about all things ocrelizumab, touching on many of the points that I discussed with Dr. Chin. A big thanks goes out to Genentech and Dr. Peter Chin for allowing me the chance to conduct this rather expansive interview.

Until next time…

.

Ocrevus: Dialogue Between Two Neurologists

Yes, folks, another post on Ocrevus. Hope I’m not beating a dead horse here, but I feel this is a very important subject given the amount of hyperbolic press coverage this newly FDA approved drug has received. The Ocrevus picture is a complicated one, especially for patients with progressive MS. It’s now the only approved drug for this form of the disease, which is a good thing. Unfortunately, there are still questions regarding the efficacy and risk associated with Ocrevus when used on the progressive MS population. Much of these questions can be accounted for by the drugs newness to the market because its risk/reward profile in a real-world setting has not yet been established. While this is true of all new drugs, the fact that the progressive MS population is clamoring for treatment options puts these uncertainties under a bright spotlight.

I first read the below email exchange between two MS neurologists about a week ago on the invaluable MS Research Blog (click here), which is written by the MS neurologists and researchers at the Barts and London School of Medicine in Great Britain. The neurologist who posted this exchange is Dr. Giovanni Giovanonni, who was one of the co-authors of the Ocrevus progressive MS trial research paper. The other neuro involved in the exchange preferred to keep their anonymity. I posted a comment to Dr. Giovanni asking if I could repost this in Wheelchair Kamikaze to give it further exposure, and he agreed. A big thank you to him.

Here then, is the dialogue on the use of Ocrevus in PPMS between Dr. Giovanonni and his anonymous colleague. Just to be clear, in all the verbiage between the linebreaks "I" refers to Dr. Giovanonni, and "his/her" refers to the other neurologist. NEJM is the New England Journal Of Medicine, in which the Ocrevus PPMS trial results were published. I’ll add my two cents at the end of this post.

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I have started-up another email exchange with a colleague about the ORATORIO (ocrelizumab in PPMS) study. I have asked him/her if we could have this debate in the open on the blog, but he/she has asked to remain anonymous.

When I respond to MS-related questions that may be of interest to the broader community I prefer to answer them in the open, which is why I have redacted the discussion and posted it below:

The following are his/her primary questions:

'You were a co-author on the ocrelizumab in PPMS NEJM manuscript, which didn’t really address the issue of age/inflammatory activity as markers for treatment response. Both the rituximab data in OLYMPUS and the Gadolinium data in the supplement of the NEJM article indicate that the population that benefits is the young patient with inflammatory activity. B cell depletion is not benign, especially in the older population, and the ocrelizumab manuscript infers that all PPMS patients should be treated with ocrelizumab. Are you really treating all of your PPMS patients with B cell depletion, and, if not, why didn’t you push for more discussion about this issue in the NEJM paper?'

My response:

We tried to restrict the trial population as much as possible to mirror that of the responder subgroup in OLYMPUS (rituximab in PPMS) study. Please note the following specific inclusion criteria for the trial:

Age cut-off of 55 years of age

Disease duration of symptoms of less than 15 years in patients with an EDSS score of more than 5.0 at screening or less than 10 years in patients with an EDSS score of 5.0 or less at screening

Documented history or the presence at screening of an elevated IgG index or at least one IgG oligoclonal band detected in the cerebrospinal fluid

​The presence of absence of Gd-enhancing lesions was not part of the inclusion criteria and hence should not be used to select patients for ocrelizumab treatment in the real-life situation. The detection of Gd-enhancing lesions also depends on the frequency of imaging. If you are going to select patients for treatment I suggest you use the the three inclusion criteria above as your guide. I predict that these will probably exclude 70% of a typical PPMS clinic population.

Please note that the trial population in the ORATORIO study was not typical of other PPMS trials; the population was younger, less disabled, had higher proportion with Gd-enhancing lesions at baseline and higher on study number of relapse​s. As I have said before there were strong trends in both the Gd+ve and Gd-ve cohorts, therefore, we shouldn't limit treatment to patients with Gd-enhancing lesions only. If we did this we would be denying many patients access to an effective treatment.

I personally don't buy into MS being 2 or 3 diseases. MS is one disease and PPMS is simply more advanced MS; if patients are active they should be offered treatment regardless of their presenting clinical phenotype.


Regarding my own practice. We can't use rituximab in the UK; the NHS won't pay for it and are unlikely to pay for ocrelizumab either. NICE will assess the cost-effectiveness of ocrelizumab based on its price for relapsing-forms of MS and in PPMS ocrelizumab will be compared to best-supportive care. The latter means ocrelizumab is unlikely to pass the NICE cost-effectiveness threshold. I am hoping that Roche, who will be marketing ocrelizumab in Europe, approach NICE and the NHS to discuss differential pricing and to offer ocrelizumab at a cheaper price for patients with PPMS. Differential pricing is a 'hot potatoe' and I am not sure the NHS is ready for it; but I live in hope for my patients.

Please note ocrelizumab has yet to be licensed in Europe and we can't assume its license will be the same as the US.

At present we offer our patients with active PPMS off-label cladribine, a relatively cheap B-cell depleting agent. Like all DMTs it is a choice and not all patients take-up the offer. I am also aware that in the US a large number of neurologists are still using low-dose methotrexate in PPMS.

I am not sure we have enough data on B-cell depletion in PPMS to make a call on whether it is benign or non-benign. Hopefully, good quality safety data will emerge from post-marketing surveillance studies. I suspect as with all immunosuppressive therapies it won't be benign. I would recommend telling all your patients about infusion reactions, the herpetic infection risk, the possible malignancy risk and the likelihood that in time they may develop hypogammaglobulinaemia and need Ig-replacement therapy. Please note we have a large amount of clinical experience in children with agammaglobulineamia and these kids do well long-term, as long as we keep the Ig levels normal.

I am not sure you are correct in suggesting that we are recommending ocrelizumab for all-comers. The trial population defines the group we are advocating its use in. I am surprised the FDA did not include the CSF findings in the label. If I was a regulator I would state that CSF-ve PPMS should not be treated with ocrelizumab.


Regarding discussion in the NEJM paper; the editors of the NEJM essentially cull all speculative discussion and limit the discussion to issues in the trial. NEJM editors are renowned for rewriting submitted papers to keep them consistent for style. The NEJM article is not the forum for the kind of discussion you want to have. I suggest we have this discussion on the blog.

His/her response:

'Thanks for your prompt and thoughtful response. It was very helpful. When do you think we’ll be able to see the age cutoffs for the study? Given that the average age for the study was 45 (and for OLYMPUS it was much higher—about 50), there should be enough patients who entered the study between 50 and 55, to know whether the relatively small treatment effect in the whole group was made up primarily of those under 50. I would certainly like for my older PPMS patients to avoid the potential adverse effects of this drug if there is no clear benefit for this group.

I agree with you about MS being one disease( except possibly for unusual outliers, like the NMO story). So, wouldn’t you expect B cell depletion to work for the younger, more active SPMS patients, too?'

My second response:


There are numerous post-hoc subgroup analyses that are ongoing. I will ask the trial team to include your question about age on the list.


Regarding SPMS; yes, I would expect B cell depletion to work for SPMS as well. I wouldn't limit it to young, or early, SPMS either. Based on our length-dependent axonopathy hypothesis I would even expect patients in wheelchairs to benefit, however, the benefit will be limited to arm and bulbar function. The latter is why we are lobbying Roche to do a trial of ocrelizumab in more advanced MS, with the primary outcome being upper limb function.

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Just a few points that grabbed my attention when I first read this exchange: first, I was surprised to read that the Ocrevus PPMS trial was specifically designed to test the drug on patients identified as likely responders, based on the “failed” rituximab PPMS trials, which were held about 10 years ago. Even though that trial had been officially deemed unsuccessful, a subset of patients were identified who did respond well to the drug (younger, less disabled, shorter disease duration). Although I highly suspected that the Ocrevus trial was intentionally frontloaded with likely responders, I’d never before come cross info confirming my suspicions. I’m not aware of any other study that has been designed in such a fashion. I believe most drug trials try to mirror the general demographic makeup of the patient population in question, although almost all MS trials exclude patients with higher degrees of disability. Due to this trial design, Dr. Giovanonni  states that he’s surprised the FDA didn’t put some sort of prescribing restrictions on the Ocrevus label.

I also found it quite interesting that Dr. Giovanonni states that the prescribing guidelines for the drug, if based on the Ocrevus trial design, would generally exclude 70% of the PPMS population. This in the face of the FDA giving a blanket approval for Ocrevus to treat PPMS with no restrictions whatsoever. While I fully understand why many PPMS patients are anxiously awaiting being offered the drug, I fear that many may have unreasonably high expectations based on the breathless press coverage that greeted the Ocrevus FDA approval. Of course, there is the “any port in a storm” factor. With the dearth of other available treatment options, why not give the drug a shot, especially if a patient finds themselves being ravaged by the disease? It is, of course, up to each patient to decide how aggressively they want to treat their illness, and their tolerance for risk.

Dr. Giovanonni also makes mention of hypogammaglobulinaemia, a general term for a patient having an insufficient number of antibodies in their bloodstream to fend off infections. While it makes sense that Ocrevus could cause this condition, since the drug wipes out a patient’s B cell population and B cells produce antibodies, I hadn’t heard of this being of much concern. Rituxan (rituximab) also obliterates most B cells, and that drug has been used off label to treat MS and other autoimmune diseases for years, to the best of my knowledge without necessitating supplementation of patients’ antibodies via the use of IVIG infusions. PLEASE NOTE: Dr. G has explained, in the comments section below, that long term Rituximab therapy does indeed cause this antibody deficiency. I stand corrected. Thank you, Dr. Giovannoni. 

Lastly, I found it intriguing that this drug might not be made available to PPMS patients in Great Britain, based on its cost-effectiveness versus supportive care. This means that in the eyes of the NHS, Great Britain’s national healthcare system, the relative effectiveness (or lack thereof) of Ocrevus in treating PPMS may not warrant its approval for use, simply because supportive care is less expensive and the impact of Ocrevus on the disease is minimal enough to disqualify it based on the drug’s high price tag.

Having said that, let's not forget that slowing the progression of disease, even if only for a portion of the PPMS population, is no small feat. In addition, the beneficial effects of Ocrevus may accumulate over time, a data point that wouldn't have been caught during the short two-year clinical trial window. Any slowdown in the progression of disability provides patients valuable time during which more effective treatments work their way through the pipeline. While I have concerns about the drug itself, my primary beef is with the way the drug has been portrayed in the media, with eye-popping headlines and hyperbolic coverage by reporters without the depth or breath of experience to look much past the pharmaceutical company press releases. Let's hope that all MS neuros do their due diligence regarding Ocrevus, and keep their patients well-informed about reasonable expectations of benefit and also the downside potential of the drug. It's always important to keep in mind that doing nothing has tremendous proven downside potential, as well.

In short, while Ocrevus does appear to be quite potent in treating relapsing MS, those with progressive MS should likely keep their expectations in line with what was seen in the PPMS trial results. The drug displayed a 25% slowdown in the rate of disease progression, which although not insignificant is certainly not the miracle that the media has made it out to be. Patients shouldn’t expect Ocrevus to reverse their symptoms, or even stop the progression of their disease. Make no mistake, slowing down progression is a very good thing, but according to the above dialogue many PPMS patients may not even see that by way of benefit. Of course, there is always the possibility that the drug proves to be more effective in clinical use than was seen in the phase 3 trials, which is something we have seen with several other drugs.

All that being said, please allow me this one brief little editorial interlude:

HEY, ALL YOU MS NEUROLOGISTS  OUT THERE! STOP STUFFING YOUR POCKETS WITH PHARMACEUTICAL COMPANY MONEY AND START LOOKING FOR THE ACTUAL CAUSE OF THIS DAMNED DISEASE! ENOUGH WITH THE “TREATMENTS” WITH POTENTIALLY HORRIFIC SIDE EFFECTS! WE WANT CURES, DAMMIT! AND UNLESS YOU FOLKS STOP LOOKING FOR NEWER AND FANCIER WAYS OF TINKERING WITH THE HUMAN IMMUNE SYSTEM AND START LOOKING FOR THE ACTUAL REASON WHY THE MULTIPLE SCLEROSIS IMMUNE SYSTEM GOES BONKERS, WE WILL NEVER, EVER, GET A CURE! AN IMMUNE SYSTEM ATTACKING ITS OWN BODY IS A SYMPTOM, NOT A CAUSE! WE PATIENTS ARE SICK AND TIRED OF BEING SICK AND TIRED, AND IF WE WEREN’T SO SICK AND TIRED WE MIGHT AT THIS VERY MOMENT BE FORMING LYNCH MOBS! SO GET WITH IT, OR ELSE!!! WHEELCHAIRS CAN BE USED AS DEADLY WEAPONS!!! AND DON'T EVEN THINK OF ASKING ME HOW I KNOW THAT!!!

Okay, feeling a bit calmer now… And, yes, I realize there are MS researchers and neuros who aren’t inflating their incomes with legal pharmaceutical company bribery while their patients clamor for truly momentous breakthroughs. Those folks should be applauded, along with those pursuing creative approaches for tackling multiple sclerosis. As for the others, well, I still want/need their help, so I better keep my mouth shut…