What happened

Shares of Amneal Pharmaceuticals (AMRX -0.51%) were down more than 13% as of 12:45 p.m. ET on Wednesday after the pharmaceutical company announced both positive and negative news regarding its clinical pipeline. The stock is still up more than 30% this year.

So what

Amneal operates in generic and specialty therapies segments and has roughly 270 products. Its specialty segment includes a portfolio that focuses on central nervous system and endocrine disorders.

Amneal said in an announcement on Tuesday that the company had launched its generic for narcolepsy treatment Xyrem, made by Jazz Pharmaceuticals, but Amneal also said it had received a complete response letter (CRL) from the Food and Drug Administration (FDA) regarding its New Drug Application (NDA) for IPX203 to treat Parkinson's disease.

In the FDA's CRL, it said that only the adequate safety of levodopa, one of the therapies in IPX203, had been proven, but the other, carbidopa, had not been established. The letter didn't address the specific safety concerns regarding carbidopa or its manufacturing. The company said it would work with the FDA to address the concerns raised in the letter. 

IPX203's NDA submission is based on a phase 3 trial that found the drug's extended release formula produced more "good on" time and less "off" time for Parkinson's patients, compared to immediate release carbidopa/levodopa.

Now what

The CRL is likely a temporary setback as Amneal has had a great couple of years regarding generic drug approvals, including 26 launches last year. On Tuesday, it also said the FDA had approved five complex generics in the second quarter. They include ones that mimic birth control therapy Depo-Provera and sedation drug Precedex from Pfizer, along with Arranon, a leukemia and lymphoma therapy from Novartis, and Aczone, an acne therapy from Spanish pharmaceutical company Almirall, as well as allergy nasal spray Nasonex, from Organon. In the first quarter, Amneal reported revenue of $558 million, up 12% year over year, with an earnings-per-share (EPS) loss of $0.05, compared to an EPS loss of $0.01 in the same period a year ago.