On Wednesday, Inside Value pick Pfizer (NYSE:PFE) threw Adolor (NASDAQ:ADLR) a bit of a lifeline after signing a modest collaboration deal with the smaller pharma. The deal, worth $31.9 million in upfront cash and potential milestone payments of $232.5 million, gives Pfizer worldwide marketing rights to two of Adolor's pain-drug candidates.

Adolor's two pain drugs are known as delta opioid agonists, which stimulate a pain-related receptor in cells in hopes of modulating pain sensations. There are no currently approved pain drugs using this target, and Adolor hopes that its delta agonists will become the first to make it to market.

Earlier in the year, Adolor advanced its lead delta opioid agonist into phase 2a testing. Its second delta agonist is slated to begin phase 1 studies in the first quarter of next year.

For Pfizer, this deal is a very cheap call option on Adolor's pain-drug franchise. For Adolor, it's a smart way to conserve its cash in case the FDA is negative on its Feb. 10 Entereg marketing application for postoperative ileus (POI) and wants more clinical trial work for this indication.

Even with this collaboration, Adolor's near- and intermediate-term futures are both highly tied to the success or failure of the POI Entereg advisory panel vote and regulatory decision. No clinical trials are under way for Entereg in POI or in the much more lucrative opioid-induced constipation indication, which partner GlaxoSmithKline (NYSE:GSK) was focused on, so a third FDA denial in POI will likely mean the end of the drug for years.

I was excited about Adolor's prospects before the new safety issues popped up with Entereg earlier in the year. This deal with Pfizer isn't enough to rekindle my excitement about shares of Adolor, but at least it keeps the drugmaker as a valid watch-list candidate even if Entereg hits more stumbling blocks.