Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Agenus (NASDAQ:AGEN) have popped by more than 31% as of this writing after the small development-stage  biotech company announced a "global alliance"  with larger biotech Incyte (NASDAQ:INCY).

So what: The Incyte-Agenus partnership will cover global licensing, development, and commercialization for drugs developed using Agenus' Retrocyte Display antibody discovery platform. It will initially focus on developing checkpoint modular antibodies to be used against GITR, OX40, LAG-3, and TIM-3. The first two antibodies (for GITR and OX40) will be developed and sold on a 50-50 basis, with each company bearing an equal share of costs and profits. The latter two antibodies will be funded wholly by Incyte, with Agenus eligible for milestone and royalty payments. The earliest trials of these programs are expected to start next year.

Now what: Incyte has agreed to pay Agenus $25 million up front, and will also purchase 7.76 million shares that Agenus will issue at a cost of roughly $4.51 per share. This share purchase agreement has already profited Incyte by approximately $6.4 million after today's pop, and will make the company an 11% stakeholder in Agenus after the dilution. Agenus is also eligible for up to $155 million per antibody in development, not including royalty payments, and could earn more if the two companies agree to collaborate on any other developments.

The $25 million payment alone is nearly five times Agenus' reported trailing 12-month revenue, and the backing of a larger biotech with deeper pockets will be enormously helpful for Agenus' research efforts. This partnership makes Agenus worth watching, although it's still too early to say how viable any of these new products might be on the global pharmaceutical marketplace.