FDA Updates: Keytruda News Leads the Week

Another FDA approval and two additional applications for Keytruda have been submitted; a generic for Chantix and a sleep disorder treatment is approved; and a complete response letter has been issued for an anemia therapy.

In Keytruda news: An approval for combination treatment for renal cell carcinoma and sBLAs for renal cell and endometrial carcinoma

The FDA has approved a new supplemental biologics license application (sBLA) for Keytruda (pembrolizumab), Merck’s anti-PD-1 therapy. This approval is for the combination of Keytruda and Eisai’s Lenvima (lenvatinib) orally available multiple receptor tyrosine for the first-line treatment of adult patients with advanced renal cell carcinoma (RCC). The approval is based on results from the pivotal phase 3 CLEAR/KEYNOTE-581 trial, in which the combination demonstrated statistically significant improvements versus sunitinib in the efficacy outcome measures of progression-free survival, overall survivalmand confirmed objective response rate.

The FDA has accepted and granted priority review for a new sBLA for Keytruda as an adjuvant treatment of patients with renal cell carcinoma (RCC) at intermediate-high or high risk of recurrence following surgical removal of a kidney. This application is based on the pivotal phase 3 KEYNOTE-564 trial, in which Keytruda demonstrated a statistically significant and clinically meaningful improvement in disease-free survival compared with placebo. The FDA has set a decision date of December 10, 2021.

Additionally, Merck has submitted an sBLA a single agent for the treatment of patients with advanced endometrial carcinoma that is microsatellite instability-high (MSI-H) or mismatch repair deficient, who have disease progression following prior systemic therapy. The application is based on overall response data from two cohorts of the KEYNOTE-158 trial, which will be presented for the first time at the European Society for Medical Oncology Congress 2021. The FDA has set a decision date of March 28, 2022.

FDA approves generic of Chantix

The FDA has approved the first generic of Chantix (varenicline), Pfizer's smoking cessation product. Developed by Par Pharmaceutical, which is part of Endo International, the generic varenicline tablets, 0.5 mg and 1 mg, was approved August 11, 2021.

This generic approval comes just a month after Pfizer stopped distribution and initiated a recall of Chantix because of high levels of nitrosamine impurity, called N-nitroso-varenicline. N-nitroso-varenicline may be associated with a potential increased cancer risk in humans. Pfizer expanded its initiall recall from nine lots to 12 lots.

The FDA allowed temporary importation of a generic from Canada to help meet the demand. Apotex Corp. initiated importation of Apo-Varenicline 0.5 mg and 1 mg tablets into the U.S. market to address a drug shortage.

Related: Apotex to Import Generic of Chantix from Canada

Apo-Varenicline is the varenicline tartrate product approved by Health Canada as a generic equivalent to Champix tablets manufactured by Pfizer Canada. Champix is the brand name of Chantix in Canada.

FDA approves sleep disorder drug

The FDA has approved Jazz Pharmaceuticals’ Xywav (calcium, magnesium, potassium, and sodium oxybates) oral solution for the treatment of idiopathic hypersomnia in adults. The company plans to make Xywav available to patients with idiopathic hypersomnia later this year following the implementation of a risk evaluation and mitigation strategies plan.

Idiopathic hypersomnia is a neurologic sleep disorder characterized by chronic excessive daytime sleepiness and the inability to stay awake and alert during the day. An estimated 37,000 people in the United States have been diagnosed with this condition and are actively seeking health care treatment, according to Jazz Pharmaceuticals.

Xywav is the first medication approved to treat idiopathic hypersomnia.

The FDA had issued fast track designation for Xywav in September 2020, as well as priority review designation.

FDA issues CRL for FibroGen’s roxadustat

FibroGen has received a complete response letter from the FDA for roxadustat for the treatment of anemia of chronic kidney disease. The agency has requested that an additional clinical study of roxadustat be conducted prior to resubmission.

The response letter comes after a July decision by the Cardiovascular and Renal Drugs Advisory Committee to not recommend approval of roxadustat. Panelists cited safety issues in two votes against approval: 12-2 in patients who are on dialysis and 13-1 in patients who not on dialysis. Roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, which aim to restore production of the hormone erythropoietin and improve iron regulation. Currently, the condition is treated by injections of epoetin alpha and darbepoetin alpha.