Several new specialty medications are expected to be approved in the remainder of 2010. New, infused therapies to treat gout and lupus may enter the market. The FDA just approved the first oral, disease-modifying drug for multiple sclerosis and should soon approve the second. In addition, the first medication approved to treat HIV-related lipodystrophy is expected to gain FDA approval. More information about these specialty medications follow.
Krystexxa (pegloticase) is a recombinant, pegylated formulation of porcine uricase (urate oxidase) that lowers levels of uric acid in the blood. Krystexxa was approved by the FDA on September 14, 2010. It is administered every 2 weeks as an intravenous (IV) infusion. Krystexxa is approved for the treatment of chronic gout in patients who are refractory to conventional therapy such as xanthine oxidase inhibitors (eg allopurinol). There are about 100,000 patients in the United States who will be candidates for treatment with Krystexxa.
It’s estimated that Krystexxa will cost $50,000 per patient for one year of therapy. It was approved with a Risk Evaluation and Mitigation Strategy (REMS) that notifies patients and prescribers about the risks of severe infusion reactions and possible anaphylaxis.
Benlysta (belimumab) may be the first medication approved to treat lupus in more than 50 years. It is a fully human monoclonal antibody that inhibits the biologic activity of B-lymphocyte stimulator (BLyS), a protein required for the development of B lymphocytes into mature plasma B cells. Elevated levels of BLyS are thought to contribute to the production of autoantibodies. After an induction phase, Benlysta is administered as a monthly IV infusion. It is in development to treat patients with systemic lupus erythematosus (SLE). Approximately 100,000 patients in the United States will be candidates for treatment with Benlysta. It is expected to cost between $25,000 and $50,000 per year. The FDA will likely approve Benlysta by December 10, 2010. The medication is also in earlyphase development for the treatment of rheumatoid arthritis.
Gilenya (fingolimod) and Movectro (cladribine) are oral, disease-modifying drugs for the treatment of multiple sclerosis (MS). Gilenya was approved by the FDA September 22, 2010; Movectro is still in development. While the mechanisms for these medications differ, they are both very effective in reducing relapse rates in patients with relapsing remitting MS (54% to 60%). However, both Gilenya and Movectro do carry risks. Gilenya use has been associated with significant drops in heart rate, macular edema, and evaluations in liver enzymes. Movectro may suppress white blood cells, thereby increasing the the risk of serious infections. Gilenya was approved with a REMS program to inform patients and health care professionals about the risks of using it in the treatment of relapsing forms of MS. Movectro will also likely be approved with a REMS program due to its safety profile.
Gilenya will cost cost as much as $48,000 annually. The FDA is expected to approve Movectro by December 8, 2010. It is possible that these medications will be used in the first-line setting before the injectable biologic medications that are currently on the market to treat MS.
Egrifta (tesamorelin) is a growth hormone-releasing hormone (GHRH) receptor agonist in development for the treatment of HIV-related lipodystrophy. It works by reducing visceral fat tissue without reducing subcutaneous fat tissue. It is administered once daily by subcutaneous injection. Lipodystrophy, or abnormal fat accumulation, can be a side effect of HIV protease inhibitors. The HIV virus itself may also contribute to a patient’s lipodystrophy. Currently, there are no FDA-approved medications for this condition.
It is estimated that anywhere from 200,000 to 800,000 patients in the United States have HIV-related lipodystrophy. In June 2010, an FDA advisory panel voted unanimously in favor of the approval of Egrifta. The FDA is expected to approve this medication in late October.
About the Author
Dr. Tharaldson is Senior Clinical Consultant, Emerging Therapeutics, at Express Scripts.