What happened
Shares of Nektar Therapeutics (NKTR) were crashing 35.2% lower as of 10:51 a.m. ET on Monday. The steep decline came after Nektar and Bristol Myers Squibb (BMY 0.92%) announced that they were ending the development program for bempegaldesleukin (bempeg) in combination with Opdivo. This decision was based on dismal results from pre-planned analyses of two clinical studies evaluating the combo.
So what
An independent data-monitoring committee for the phase 3 Pivot-09 study evaluating bempeg and Opdivo in treating renal cell carcinoma found that the combo therapy didn't achieve an objective response rate or overall survival rate high enough to warrant continuing the study. It was a similar story in the phase 2 Pivot-10 study of the two drugs in treating urothelial carcinoma. The combo therapy didn't reach an efficacy threshold needed to justify moving forward with the study.
The results were so bad that Nektar and Bristol Myers Squibb decided to throw in the towel on all other clinical studies featuring the bempeg/Opdivo combo. These now-discontinued studies include a phase 1/2 trial in combination with TKI therapy as a first-line treatment for renal cell carcinoma and a phase 1/2 study in treating pediatric tumors.
It's not surprising that Nektar's shares plunged so much today. Bempeg was the company's lead pipeline candidate. However, the biotech stock had already fallen more than 50% year to date. Last month, Nektar and Bristol Myers Squibb announced that the phase 3 Pivot IO-001 study evaluating bempeg and Opdivo in treating metastatic melanoma would be discontinued because of disappointing results.
Now what
Nektar's fortunes didn't totally hinge on bempeg. The company has two products on the market with partners AstraZeneca and Takeda. Several other approved medicines also use Nektar's technology.
However, Nektar's pipeline doesn't have any other late-stage programs with bempeg no longer in the mix. Nektar will now be in rebuilding mode. Investors will probably be better off staying on the sidelines with the stock in the meantime.