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What: Shares of NewLink Genetics Corporation (NASDAQ:NLNK), a biopharmaceutical company developing immuno-oncology therapies, sank 27.6% last month, according to data from S&P Global Market Intelligence. A large part of its clinical-stage program came into question after announcing a phase 3 failure in a pancreatic cancer study.

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So what: NewLink's self-described wide range of immuno-oncology portfolio candidates became much smaller when algenpantucel-L (HyperAcute-Pancreas Immunotherapy) added to a standard chemotherapy regimen failed to improve outcomes in a group of patients with surgically resected pancreatic cancer.

In fact, median survival of 30.4 months in the control arm (the group that didn't include NewLink's experimental drug) was 3.1 months longer. The difference could be due to chance, but it doesn't bode well for the company's HyperAcute Cellular Immunotherapy platform. It's designed to produce candidates composed of human cancer cells that are tumor- but not patient-specific, that would provide off-the-shelf convenience that other cellular therapies lack.

Now what: This failure in resected pancreatic cancer patients is discouraging on several levels. Most importantly, there is a dearth of effective options, and NewLink should be given credit for even making an attempt in this famously difficult-to-treat patient population.

The recent failure also casts a dark shadow on a more recent phase 3 trial with about 302 unresectable or borderline resectable pancreatic cancer patients adding the same experimental drug, algenpantucel-L, to two common chemotherapy cocktails.

Results from the trial are expected in December, and although I'll keep my fingers crossed, I'm not expecting success. At the end of May, NewLink terminated its agreement with WuXi, the company it had hired to supply it with algenpantucel-L for commercial sale.

A phase 2 trial with another HyperAcute-based immunotherapy candidate, tergenpumatucel-L in lung cancer, produced some positive results a few years ago. NewLink is running a larger, 135-patient phase 2/3 trial to measure it against common chemotherapies in similar patients. The trial's estimated completion date is this December, but given what we've seen recently with its HyperAcute-based candidates, optimism is in short supply.

NewLink is down but not out. It has an oral immunotherapy drug, indoximod, intended to block a pathway tumor's use to suppress immune system attack. At a recent scientific conference, the company presented some positive response rates from early trials combining the IDO inhibitor, with Keytruda from Merck & Co., and Yervoy from Bristol-Myers Squibb. Indoximod is also under investigation in combination with Roche's therapies in a phase 2 pancreatic cancer study.

It's far too early to draw conclusions, but indoximod could have a future in combination with some of these popular cancer therapies. When the company last reported, it had about $177 million in cash, which should buy it enough time to find out before it needs to raise equity again.

There are biotechs far worse off than NewLink, but it's probably best to wait and see with this one.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.