Sunovion's COPD ambitions dented as FDA rejects phase 3 candidate

Sunovion released some devastating news ahead of the holiday weekend, as the FDA threw a wrench into its plans to bring a new drug for chronic obstructive pulmonary disease (COPD) to market.

The Sumitomo Dainippon subsidiary hasn't yet revealed what prompted the Complete Response Letter from the regulator, saying simply that it isn't asking for any additional clinical trials to be carried out for SUN-101, a nebulized formulation of the long-acting muscarinic antagonist glycopyrrolate.

It's a big blow to Sunovion's ambitions to grow a sizable portfolio in COPD, a strategic priority for the firm. It already sells Brovana—a twice-daily nebulized formulation of a long-acting beta agonist aformoterol—and recently acquired U.S. rights to a trio of Novartis respiratory meds in a bid to bulk up in COPD ahead of SUN-101's launch.

If approved, SUN-101 would have been the first nebulized LAMA approved for the treatment of COPD in the U.S., but the delay hands an opportunity to Theravance Biopharma and its partner Mylan to catch up with their rival candidate revefenacin, according to an Endpoints article. Theravance completed enrolment in its phase 3 program for the once-daily drug last June.

Sunovion reported encouraging phase 3 data for SUN-101 delivered using its portable eFlow nebulizer device—developed by Germany's PARI Pharma—as a twice-daily maintenance treatment for COPD. The device acts more quickly than a standard jet nebulizer, cutting the delivery time for the drug to two or three minutes rather than 10.

In late-stage testing, the drug/device combination achieved a statistically significant change from baseline in forced expiratory volume in one second (FEV1 — a lung function measurement) at week 12 for treatment groups versus placebo. 

"Sunovion will work with the FDA to determine an appropriate path forward," said the Marlborough, MA-based biotech in a statement. "We are confident in SUN-101/eFlow and are committed to bringing this innovative therapy to COPD patients in the U.S. as quickly as possible."

Meanwhile, Sunovion has chalked up other acquisitions in recent months to bolster its portfolio. Last year it bought, and paid $624 million for Canada's Cynapsus, adding phase 3 Parkinson's drug APL-130277 (oral apomorphine) designed to tackle the troublesome and hard-to-manage 'off' episodes in the disease.

Injectable apomorphine can be used for off episodes but its cost and the need to use other drugs to manage side effects has limited its appeal, and analysts have suggested Sunovion could expand the market for the drug significantly with its new under-the-tongue formulation.