FDA approves Novantrone for secondary progressive multiple sclerosis

Immunex' Novantrone (mitoxantrone for injection) has become the firstdrug to be approved by the US Food and Drug Administration for the treatment of patients with the secondary-progressive form of multiple sclerosis. Novantrone is indicated for reducing neurologic disability and/or the frequency of clinical relapses with SPMS, as well as the progressive-relapsing and worsening relapsing-remitting forms of the disease.

The full approval lays to rest speculation that Novantrone's approval for MS may have been delayed by the FDA's concerns about its potential to cause cardiotoxicity, first raised at an advisory committee meeting on the drug earlier this year (Marketletter February 7). Although no congestive heart failure was reported in trials of the drug, the company notes that there is potential for cardiac changes with Novantrone treatment, and it has recommended monitoring of patients receiving the product. Serious cardiac conditions can be limited by discontinuing treatment at a cumulative dose of 140mg/m2, so patients should receive no more than eight to 12 doses over two to three years.

The new indication is based on results from a two-year Phase III trial in which Novantrone, at a dose of 12 mg/m2, was administered by short intravenous infusion once every three months. This trial demonstrated that the drug had a statistically-significant impact on prolonging time to first treated relapse and on delaying disability progression in patients with SPMS or PRMS. There was also a significant reduction in the mean number of treated relapses, as well as a reduction in the number of patients who had new MS lesions seen on magnetic resonance imaging.