Atara Biotherapeutics, a Thousand Oaks firm that emerged last year with major Silicon Valley backers and licenses to develop six Amgen assets, has raised $38.5 million to pursue treatments for dialysis complications and ovarian cancer.

The deal represents one of the first major forays into so-called out-licensing for Amgen, which has tended to either buy new treatments in deals, like its $10.4 billion purchase of Onyx Pharmaceuticals, or develop them internally, like its bone drug denosumab.

Amgen is aiming for a new kidney and cancer blockbuster drugs with Atara. Amgen CEO Robert Bradway has plugged holes in with the company’s anticipated $18.3 billion revenue stream and its new bone drugs are breaking the billion-dollar mark, but pressure remains to find new sellers to keep up the momentum – and keep up the dividend increases.

Atara emerged from stealth mode in late 2012 with an undisclosed amount of capital from Kleiner Perkins Caufield & Byers, which took a majority position. Amgen took a minority stake. The two said the firm would be led by Isaac Ciechanover, a Kleiner Perkins partner and medical doctor, but did not talk publicly about which drugs it would pursue.

But over the past 15 months, research has progressed rapidly, and Atara said the new capital will go toward its two lead programs, called PINTA 745 and STM 434. PINTA 475, which is further along in the trial process, would a treat a common dialysis complication called protein energy wasting, building on one of Amgen’s core markets for kidney disease drugs. The other drug, STM 434, would treat ovarian cancer and other solid tumors.

“We founded Atara with the goal of accelerating the development of novel biologic compounds to bring meaningful therapeutic advances to conditions underserved by innovation in recent years,” Ciechanover said in statement. “This financing allows us to advance our pipeline and moves us closer to achieving our mission of addressing substantial unmet medical needs.”

In the most recent round of financing, investors Amgen Ventures, fellow biotech firm Celgene Corp. and EcoR1 Capital, joined existing investors Alexandria Venture Investments, DAG Ventures, Domain Associates and Kleiner Perkins.