FDA Updates for Week of March 25: Two Approvals for PAH

FDA Approves Merck’s Drug for Pulmonary Arterial Hypertension

The FDA has approved Winrevair (sotatercept-csr), Merck’s therapy to treat adults with pulmonary arterial hypertension (PAH). PAH is caused by the growth of cells in the arterial walls in the lung, leading to narrowing and abnormal constriction. Winrevair is a first-in-class activin signaling inhibitor. It is given once every three weeks by subcutaneous injection. Merck officials said in a press release that Winrevair will be available through select specialty pharmacies in the United States by the end of April.

The price of Winrevair is $14,000 per vial, and Merck officials said they expect patients will be mostly in Medicare and Medicaid patients. About a third or more of patients are expected in commercial plans.

The approval of Winrevair is based on the results of the STELLAR phase 3 trial. In the trial, Winrevair given with a background therapy demonstrated a statistically significant and clinically meaningful improvement in six-minute walk distance and eight of nine secondary outcome measure. Data were presented earlier last year at the American College of Cardiology meeting and published in the New England Journal of Medicine in April 2023. In the trial, 38.9% of patients in the Winrevair group achieved improvement at week 24 compared with 10.1% in the placebo group.

FDA Approves Combination Therapy for Pulmonary Arterial Hypertension

The FDA has approved Opsynvi to treat adult patients with pulmonary arterial hypertension (PAH). Pulmonary arterial hypertension is a rare, progressive and disorder characterized by the constriction of small pulmonary arteries and elevated blood pressure in the pulmonary circulation. This blocks blood flow to the lungs. An estimated 500 to 1,000 new cases of PAH are diagnosed each year in the United States, according to the American Lung Association.

Developed by Johnson & Johnson, Opsynvi is a single-tablet combination of macitentan, an endothelin receptor antagonist (ERA), and tadalafil, a phosphodiesterase 5 (PDE5) inhibitor. Macitentan is sold by J&J under the name of Opsumit. Tadalafil is sold by both as a generic and under the brand names of Cialis for erectile dysfunctin and Adcirca for PAH by Lilly. In PAH, tadalafils help to relax blood vessels, making it easier for the heart to pump.

The list price of Opsynvi will be at parity to Opsumit, according to a spokesperson for J&J, and patients won’t have to pay any out-of-pocket costs related to separate PDE5 inhibitor prescription. The cost for Opsumit oral tablet 10 mg is around $6,662 for a supply of 15 tablets, according to Drugs.com.

FDA Approves Vemlidy for Children with Hepatitis B

The FDA has expanded the indication of Vemlidy (tenofovir alafenamide) for patients with chronic hepatitis B virus (HBV) infection. It now approved to treat pediatric patients 6 years of age and older and weighing at least 25 kg. Vemlidy is already available to treat adults and adolescents 12 years and older.

Developed by Gilead Sciences, Vemlidy is a targeted prodrug of tenofovir that was first approved by the FDA in 2016. In 2023, Vemlidy generated total worldwide sales of $862 million compared with 842 million in 2022.

Vemlidy 25 mg has a price of $1,528 for 30 tablets, according to Drugs.com. Patients with commercial insurance may be eligible for a $0 copay with an annual limit of $6,000 a year. Gilead notes in its terms and conditions that it may reduce or discontinue the copay assistance if a patient’s plan has a copay accumulator or maximizer program.

FDA Approves Vafseo for Anemia in Kidney Disease

The FDA has approved Vafseo (vadadustat) tablets to treat anemia due to chronic kidney disease (CKD) in adults who have been receiving dialysis for at least three months. About 500,000 adult patients in the United States on dialysis suffer from anemia due to chronic kidney disease. Anemia is often treated with injectable erythropoiesis-stimulating agents mostly administered at dialysis centers.

Developed by Akebia Therapeutics, Vafseo is an oral hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor. It was designed to mimic the physiologic effect of altitude on oxygen availability. At higher altitudes, the body responds to lower oxygen availability with stabilization of hypoxia-inducible factor, which can lead to increased red blood cell production and improved oxygen delivery to tissues.

Vafseo will be available in January 2025. The price has not been released, but the price will align with its value, Nicholas Grund, senior vice president and chief commercial officer, said during an investor call.

Most patients on dialysis are in Medicare and Medicaid plans that are reimbursed through bundled payments. About 40% of patients who could be treated with Vafseo have coverage through Medicare Advantage plans.

FDA Grants Full Approval to Elahere

The FDA has granted full approval for Elahere (mirvetuximab soravtansine-gynx) to treat adult patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer. It is indicated for women who have received one to three prior systemic treatment regimens.

Elahere had been granted accelerated approval in November 2022. It is an antibody-drug conjugate targeted against folate receptor alpha, a cell-surface protein highly expressed in ovarian cancer. About 35% to 40% of ovarian cancer patients express high levels of folate receptor alpha.

Elahere was developed by ImmunoGen, which AbbVie acquired in February 2024. When Elahere launched, the wholesale acquisition cost was $6,220 for one vial, and patients, typically undergo the use of three to four vials per cycle. This translates to $18,660 to $24,800 per treatment cycle.

FDA Issues CRL for Odronextamab for Lymphoma Indications

he FDA has issued complete response letters (CRLs) for Regeneron’s biologics license application (BLA) for odronextamab in patients relapsed/refractory (R/R) follicular lymphoma (FL) and in R/R diffuse large B-cell lymphoma (DLBC).

Regeneron officials said in a press release that regulators want to address an issue related enrollment status of the confirmatory trial. The company has been actively enrolling patients in multiple phase 3 trials for odronextamab as part of the OLYMPIA program. The program both dose-finding and confirmatory portions. Enrollment in the dose-finding portion has begun, but the CRLs indicate that the confirmatory portions of these trials should be under way and that the timelines to completion be agreed prior to resubmission.

Odronextamab is an investigational CD20xCD3 bispecific antibody designed to target both CD20 on cancer cells and CD3-expressing T cells.