PFE Stock Reacts To Mixed Topline Results For Seagen-Origin Cancer Drug

• Pfizer, however, highlighted encouraging trends in a key prespecified subgroup. 
• Sigvotatug vedotin is part of Pfizer’s efforts to deliver eight potential cancer drug breakthroughs by 2030.
• Pfizer acquired Seagen in 2023 for a total enterprise value of approximately $43 billion to expand its cancer pipeline.

Pfizer (PFE) shares slipped nearly 2% in after-hours trading on Monday after the company reported mixed topline results from a pivotal late-stage trial of its investigational antibody-drug conjugate sigvotatug vedotin in previously treated metastatic non-squamous non-small cell lung cancer.

The stock closed the regular session at $25.08 before falling to around $24.71 after hours, as investors digested the news that the drug failed to meet its primary endpoint of overall survival in the overall study population.

PFE Trial Results

Pfizer announced results from the SigVie-002 study, which evaluated sigvotatug vedotin versus docetaxel in 703 patients with locally advanced, unresectable or metastatic non-squamous NSCLC who had received one or more prior lines of therapy.

In the overall population, sigvotatug vedotin did not demonstrate a statistically significant improvement in overall survival compared with docetaxel. The primary endpoint was therefore not met.

However, the company highlighted encouraging trends in a key prespecified subgroup: patients who had received only one prior line of systemic therapy, representing approximately two-thirds of the enrolled population. In this second-line group, sigvotatug vedotin showed stronger signals favoring both overall survival and progression-free survival over docetaxel.

Descriptive secondary endpoints, including progression-free survival, confirmed objective response rate, and duration of response, also supported positive trends in the second-line setting, the company said. The safety profile of sigvotatug vedotin was described as manageable and consistent with earlier clinical studies.

Execs Weigh In

“Patients with previously treated advanced NSCLC are a historically difficult-to-treat population, and there is clearly more work to be done to improve the outcomes for this population,” Jeff Legos, Chief Oncology Officer, said. “Although the overall study results did not demonstrate superiority over docetaxel, it is encouraging that second-line patients treated with sigvotatug vedotin achieved strong efficacy outcomes compared to an established standard of care, alongside a manageable safety profile.”

Detailed results from SigVie-002 will be submitted for presentation at a future medical congress, Pfizer said. The company is also conducting an ongoing late-stage trial evaluating sigvotatug vedotin in combination with Merck’s blockbuster cancer drug pembrolizumab in certain first-line advanced NSCLC patients. Additional combination studies with novel agents are also underway.

Sigvotatug vedotin is part of Pfizer’s efforts to deliver eight potential cancer drug breakthroughs by 2030. It acquired Seagen in 2023 for a total enterprise value of approximately $43 billion to expand its cancer pipeline. Sigvotatug vedotin was part of the deal.

How Did PFE Retail Traders React?

On Stocktwits, retail sentiment around PFE stock stayed within the 'bullish' territory over the past 24 hours, while message volume stayed at 'high' levels.

A Stocktwits user predicted a major selloff on Tuesday.

Another justified the company’s purchase of Seagen, highlighting potential.

PFE stock has traded flat year-to-date.

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