Image source: Flickr user Stockmonkeys.com.

What: After AbbVie Inc. (ABBV 0.89%) expanded a collaboration with the company to work on therapies for cystic fibrosis, shares in Galapagos NV (GLPG -0.03%) jumped 30.5% last month, according to S&P Global Market Intelligence.

So what: On April, 29, AbbVie and Galapagos announced that the two were expanding their cystic fibrosis partnership.

Specifically, AbbVie has agreed to increase the potential milestones it will pay Galapagos for phases 1 and 2 trials to $600 million from the $350 million promised previously. The increase is due to success the two are having in creating multiple therapies that may be used in a triplet combination therapy addressing up to 90% of 80,000 patients globally diagnosed with this life-altering disease.

The companies plan to initiate human trials of triplet therapy in patients with an amenable F508del mutation beginning next year. In pre-clinical studies, triplet combinations under development have shown that they can significantly increase chloride transport when compared to Orkambi. Orkambi won approval for use in F508del patients in 2015 and in the first quarter, Vertex Pharmaceuticals (VRTX 1.43%) reported Orkambi sales of $223 million. 

Momentum stemming from the expanded partnership with AbbVie was strengthened in late May when Gilead Sciences (GILD 0.28%) announced plans to move filgotinib -- a drug for the treatment of rheumatoid arthritis that's being co-developed with Galapagos -- into phase 3 trials. A phase 3 study in rheumatoid arthritis will commence in the third quarter. Gilead Sciences also announced plans to initiate phase 3 studies of filgotinib in Crohn's disease and phase 2/3 studies in ulcerative colitis in the coming months.

Other key collaboration terms remain in place: tiered royalty payments on net sales, ranging from mid-teens to 20%.  Galapagos retains commercial rights to China and South Korea, and has an option to co-promote in Belgium, Netherlands, and Luxembourg.

Now what: Galapagos' collaborations appear to be progressing smoothly, and given that its work with AbbVie and Gilead Sciences targets billion-dollar blockbuster indications, investors are right to be encouraged.

However, investors should remember that the cystic fibrosis drugs are in the earliest stages of development, and because of that, there's no telling what the clinical outcome of trials may be. Additionally, while filgotinib has shown solid efficacy and safety in trials so far, plenty of phase 3 trials miss their mark, so there's risk associated with the Gilead Sciences program, too.

Overall, Galapagos is an incredibly intriguing company that's got top-tier partnerships and potentially top-selling medications in the works. Stashing Galapagos away in risk-tolerant portfolios could be profit-friendly over the long haul, but investors will need to expect a lot of pops and drops along the way due to how many trials it's got planned.