Tuesday, July 27, 2010

Keeping cool about ipi

Anyone who finds common cause with a patient advocacy group knows that the group itself can sometimes behave irrationally. In medicine, I closely follow what’s happening in melanoma research and education, most notably the activity of the Melanoma Research Foundation. I watch, however, with the detachment of a journalist. There’s a lot of hoo-ha in any tight circle of people, especially when cancer is involved. Emotions can run high, and perspective lost on certain important issues.

This appears to be the case with ipilumumab, about which I wrote several weeks ago. Some of the patients most of need of hope are understandably frustrated to know that it can take a new drug many months—and sometimes years—to receive approval from the Food and Drug Administration. There hasn’t been a new drug approved for treating melanoma since Bill Clinton was president, and ipi has been found in a randomized clinical trial to save lives. It should be and likely will be approved. There are, unfortunately, people dying from advanced melanoma right now who might benefit from it. Some of their advocates are furious about what they perceive as callousness and foot-dragging by the feds.

A letter-writing campaign advocated by some who frequent the MRF web site is nonetheless ill-advised. An application for expedited review has been submitted by Bristol Myers Squibb (which developed ipi), and the FDA is reviewing it. Data from the study appears to be solid, and it’s my sense that this immunotherapy drug will be approved sometime next year. This means that ipi will eventually become available to thousands more patients than have had access to it under research protocols. It's not a home run, but in baseball parlance, it should advance the base runners.

The FDA is in a perpetual no-win position. If it doesn’t move quickly enough on a new drug, then some patient groups blast it for bureaucratic delay. If it moves quickly and problems arise later, it can be blamed for sloppy work. A big show of public interest will sometimes cause the FDA to become more cautious and actually draw out its review, especially if it suspects the support has been orchestrated by those with obvious economic interests. The FDA has been burned on this in the past. The FDA’s review panel must be allowed to do its job. Ipi has serious side-effects, including a 1% mortality rate, which cannot be papered over.

The MRF’s executive director has noted that public input will be invited during the approval process, and that letters at that point may be useful. Now is not be the best time for a cascade of letter-writing, however. Patient advocates will do themselves no favor by going off half-cocked. When the time is right, I intend to write one myself.

Another drug with a high likelihood of approval in melanoma is Plexxikon’s PLX-4032, which has a completely different mechanism of action from ipi. What the two drugs do share in common is that both were rationally designed in light of the underlying science of the disease. Although there is still no data from a large randomized study for PLX-4032, early stage results were so overwhelming that its approval seems imminent.

The following statement was made by a stock analyst at seekingalpha.com:
Although ipi and PLX-4032 basically compete for the same patients, physicians will probably use both sequentially, when possible. In addition, only ~60% of melanoma patients are suitable for PLX-4032, leaving the rest of the patient population to ipi. Down the road, a combination of the two agents seems reasonable, given the unrelated mechanisms of action.
While there is good, reliable information about cancer treatment to be had, you have to be careful about your sources. There’s a wealth of knowledge and experience in the melanoma community, but it also tends to be reactionary. These are people with whom I identify, but who will act as desperate people often do, and who have been known to shoot themselves in the foot in the process.

1 comment:

Anonymous said...

Bristol-Myers Squibb could be in a position to launch ipilimumab for the treatment of second-line metastatic melanoma early next year if the recently submitted drug is granted a priority review by regulators.