OptumRx Spotlights Two Drugs That Treat Rare Liver Diseases

by Leslie Small

In OptumRx's latest Drug Pipeline Report, the UnitedHealth Group-owned PBM highlights a pair of drugs that offer long-sought treatments for two rare forms of liver disease. The drugs are Bylvay (odevixibat), which the FDA approved on July 20, and maralixibat, which the agency is expected to approve in late September.

Cost will be high:

• Bylvay, which is manufactured by Albireo Pharma, Inc., is the first drug approved for treating pruritus — or persistent itchiness — in all subtypes of progressive familial intrahepatic cholestasis, a group of three related genetic disorders.
• Mirum Pharmaceuticals, Inc.'s maralixibat, if approved, would be the first treatment for patients ages 1 year and older with Alagille Syndrome, a rare genetic disorder in which bile ducts are abnormally narrow, malformed and reduced in number.
• "It's expected that the cost for these drugs will be high given the rarity of the diseases," OptumRx's report says. The average cost per patient, per year for Bylvay is expected to be $385,000, adds Arash Sadeghi, a clinical pharmacist at OptumRx. But he also notes that "Bylvay is weight-based, so there will be differences from patient to patient."
• Because Bylvay and maralixibat work in similar ways, both drugs also being evaluated for use in other rare liver conditions, OptumRx's report notes. "Therefore, while the initial FDA applications for each are for different uses, they could eventually have mirroring indications."

Pharma invests heavily in rare disease drugs:

• "Pharmaceutical manufacturers are investing heavily in the rare disease market due to a variety of incentives," says Sadeghi. The Orphan Drug Act, he points out, "provides tax breaks and other economic incentives designed to make these niche markets more attractive to drugmakers."
• "Another incentive is the level of evidence required is usually lower for orphan conditions," Sadeghi adds. "Unlike in very common conditions where manufacturers usually need at least two studies, orphan drugs very often get approved based on one study and many times it is based on surrogate endpoints instead of hard clinical outcomes."

From RADAR on Drug Benefits