Michael J. Castine, MD
Incoming generic and biosimilar substitutes for dominant, brandname hematology drugs may lead to less costly treatment, but a lot will depend on the quality and supply of these new products, says Michael J. Castine, MD, of the Hematology Oncology Clinic of Baton Rouge, Louisiana. The use of generics and biosimilars will also be affected by the strength of newer therapies and their ability to transform cancer care, he said.
Castine believes the biggest impact on the growth of the hematology market may be the power of new drugs to reduce cancer to the status of a chronic disease. Patients are already living dramatically longer, which is in stark contrast to the days when Castine was in residency. “The growth is patients living longer and taking therapies longer, which is something that we never had before. I completed my training 20 years ago, and the average life expectancy for a chronic myeloid leukemia patient was 3 to 5 years. If you had a match, you’d have a transplant in the first year. There were very few people who survived or were cured, and now we have people walking around on Gleevec [imatinib] for 10, 12, 15 years. It’s the same with myeloma. Myeloma had a 40- to 44-month life expectancy 20 years ago, and now it’s almost out to 71 or 72 months, and that doesn’t even include the three drugs that were approved last year,” he said.
Generics and biosimilars such as are anticipated by the GBI Research report (page 24) hold the potential to reduce costs of care, but an equally likely scenario is that these drugs will be used in tandem with newer, more costly therapies, Castine said. “As patients come off these [older] drugs they’re going to be going onto novel drugs; and at the same time, novel drugs are finding their way closer and closer to front line therapy.” Gleevec appears fated for such a transition, he added. “There’s already competing data from other tyrosine kinase inhibitors: Tasigna (nilotinib) has better data up against Gleevec in the initial line of therapy.”
Even though new generics and biosimilars will cost less, hematologists may not automatically make the switch from brand name drugs, Castine said. The quality and reliability of the supply of substitute drugs also will play a role in their acceptance. The Baton Rouge clinic uses generics as much as possible, but with some of them the side effects can be more severe. This happened with a generic form of Taxotere (docetaxel), Castine said. “More women receiving Taxotere now are having skin peeling— palmar-plantar erythrodysesthesia—than I’ve ever seen with Taxotere in the past. I saw it a little bit, but now I see it a lot.” Separately, generic drugs were also suspected when platelet counts dropped among patients with colon cancer. “I had more trouble with thrombocytopenia in my patients and I couldn’t figure it out. After I saw the fourth patient within 2 days having grade 3 thrombocytopenia—they were early in treatment—I went back to talk to the nurses, and they said, ‘Yes, we’re buying generic now.’” The brand name drug was reinstituted and the problem went away, Castine said.
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