New Melanoma Drug May be Approved Soon
There are great expectations that the Food and Drug Administration (FDA) will soon approve ipilimumab for the treatment of melanoma.
Bristol-Myers Squibb Co has submitted a request to the FDA for biologics license application (BLA) for ipilimumab (proposed trade name YERVOY).
If approved, ipilimumab will be the first melanoma drug to receive FDA approval in 13 years. Ipilimumab is a new “anti-CTLA-4” drug developed jointly by Medarex and Bristol-Myers Squibb.
The biologic ipilimumab is a monoclonal antibody which binds to CTLA-4 and inhibits it from functioning. This gives the immune system freer rein to identify and eliminate melanoma cells.
The results of a large Phase III trial of 676 advanced, inoperable melanoma patients was published in 2010 in the New England Journal of Medicine. The trial found that patients who received ipilimumab lived on average 32% longer and had a 20% greater chance (45 percent vs. 25 percent) of surviving one year than those who received a melanoma vaccine alone.
The Phase III trial also found 24% were alive after two years, compared with just 14% of those treated with the other therapy.
The impact of this trial cannot be overemphasized, as ipilimumab was shown to be the first treatment ever to improve overall survival in advanced melanoma patients.
In addition to the Phase III trial, Bristol announced yesterday that a clinical trial -- known as study 024 – of ipilimumab has also met the primary endpoint of improving overall survival in previously-untreated patients with metastatic melanoma.
Study 024 assessed overall survival in unresectable stage III or stage IV melanoma patients who have not received prior therapy. Patients were either given ipilimumab 10mg/kg in combination with chemotherapy (dacarbazine) or chemotherapy alone. The study data will be submitted to the American Society of Clinical Oncology for potential presentation at the Annual Meeting in June of this year.
Side effects of ipilimumab are related primarily to the over activation of the immune system, resulting in itching, skin rash and diarrhea. In fact, ipilimumab may be more effective in patients who develop these side effects. Another idiosyncrasy of the treatment is that even in patients who ultimately see benefits, the disease may initially progress before it stabilizes or the tumor shrinks. For this reason, early clinical trials were at first deemed a failure before patients started to improve.
Melanoma is the deadliest form of skin cancer. When discovered early, it can usually be cured with surgery alone, but once it spreads (metastasizes) throughout the body, treatment options are limited. Current drug therapy for melanoma includes dacarbazine (DTIC), interleukin-2, and interferon (IFN).
Dacarbazine (DTIC) was approved in 1975. Patients on dacarbazine have a one-in-eight chance of responding to it, and no additional benefit has been achieved by combining it with other chemotherapy drugs.
In January, 1998, high-dose interleukin-2 (IL-2), an immunological therapy, was approved by the FDA for stage IV patients. It is curative in 4% of patients, but associated with very serious side effects and fatal on average for one patient in 50.
Finally, interferon (IFN) alpha-2b, another immunotherapy, was approved by the FDA in 1995 for melanoma patients who are at high risk of recurrence – stage IIB patients with primary tumors 4 mm or thicker and stage III patients with metastatic disease that has spread as far as the nearby (regional) lymph nodes. IFN alpha-2B can extend a patient’s remission (disease-free interval) to an average of 9 months, but does not lengthen overall survival. It also has significant flu-like side effects.
“This is a very exciting time in the field of melanoma,” said Perry Robins, MD, President, The Skin Cancer Foundation. “As melanoma incidence continues to rise, we are hopeful that this new therapy will extend life and improve the quality of life for those patients with metastatic melanoma.”