Array BioPharma Inc. said Wednesday it will eliminate around 50 jobs, or 20 percent of its staff positions, after Amgen Inc. ended a partnership with Array on diabetes drugs.

Array said it was informed of Amgen’s decision this week. It will regain the rights to the products the companies were developing together, including one drug in mid-stage clinical testing. The Boulder, Colo., company said it will have around 200 employees after the cuts are made.

Shares of Array fell 25 cents, or 4 percent, to $6.30 in aftermarket trading.

Amgen and Array announced a collaboration on type 2 diabetes drugs in December 2009. Amgen paid Array $60 million upfront and also agreed to fund some full-time Array employees as part of a two-year research collaboration.

The most-advanced drug the companies were developing is called ARRY-403 or AMG-151. It is designed to help the body produce more insulin. Array said Amgen recently finished a mid-stage trial and it will share results from that study soon.

The company also reported its fiscal fourth quarter results on Wednesday. Array said it lost $17.6 million, or 15 cents per share. A year ago it took a loss of $8 million, or 9 cents per share. If one-time items are excluded the company said its loss decreased to 6 cents per share from 9 cents per share. Revenue grew 23 percent, to $25.4 million from $20.7 million after Array received a license payment from Oncothyreon Inc. and a milestone payment from Novartis AG.

Analysts were expecting an adjusted loss of 13 cents per share and $16.3 million in revenue, according to FactSet. The company’s fiscal fourth quarter ended June 30.

In the fourth quarter the company took a one-time charge of $11.2 million charge for early repayment of debt.

Array said it lost $61.9 million, or 57 cents per share, in fiscal 2013 after losing $23.6 million, or 33 cents per share, in fiscal 2012. Revenue fell 18 percent, to $69.6 million from $85.1 million.