Physicochemical Laboratory Analyst

ESMO splits biotech stocks as strong cancer data face doubts. Moderna and Tango lost ground around ESMO despite encouraging cancer results, while Xencor gained favor; analysts point to different commercial hurdles. Key facts. * Latest stock moves: MRNA -0.47%; TNGX +0.84%; XNCR +2.09% at the Oct. 30, 2026 close, 20:00 GMT. * Moderna reaction: Shares fell by double digits after further ESMO data on intismeran autogene. * Tango combination: 82% response rate; 88% alive without disease progression after nine months in the studied pancreatic cancer patients. * Xencor development: 46% response rate at the highest tested XmAb819 dose; Phase 3 comparison with Fotivda planned. Moderna shares fell by double digits after its ESMO cancer-vaccine presentation, while Tango Therapeutics also declined and Xencor drew a more favorable investor response. Encouraging cancer-trial results were not enough to secure investor support at the European Society for Medical Oncology meeting. Moderna shares fell by double digits after its presentation, Tango Therapeutics declined through the conference, and Xencor received a more favorable reception. The split reflected different questions about what comes after a successful readout: whether a personalized vaccine can become a major commercial product, whether a combination treatment can withstand competition, and whether an early antibody drug can deliver efficacy without limiting side effects. Analysts detailed those concerns in coverage reported by BioPharma Dive. Moderna faces a commercial test beyond melanoma. Moderna and Merck are developing intismeran autogene, an individualized neoantigen cancer vaccine. In August, a late-stage melanoma trial showed that adding the vaccine to Keytruda after surgery could help prevent relapses, sending Moderna shares sharply higher ahead of the meeting. The ESMO details appeared to meet Wall Street's elevated expectations, but the shares still sold off. The results had been scheduled for disclosure on Oct. 24, although details leaked two days earlier. The remaining questions extend beyond the melanoma result. Investors want evidence that the treatment can work in other tumors and become commercially successful despite a complicated, personalized manufacturing process. William Blair analyst Myles Minter described the distinction as one between a highly effective melanoma treatment and a product with blockbuster potential comparable to Keytruda. Investors want evidence that the treatment can work in other tumors and become commercially successful despite a complicated, personalized manufacturing process. That leaves Moderna with separate scientific and commercial hurdles. Success after melanoma surgery supports the vaccine's clinical promise, but does not itself establish how broadly the treatment can be used or how its individualized production will translate into a business. Tango's results compete with restructuring concerns. Tango presented results for vopimetostat paired with Revolution Medicines' Rasonque in pancreatic cancer patients with certain mutations. In patients receiving treatment after earlier therapies, the regimen produced responses in 82%; 88% were alive without disease progression after nine months. Those findings drew analyst praise but failed to prevent a share-price decline during the conference. Stifel analyst Laura Prendergast said some investors may have expected a higher response rate. The clinical presentation also arrived alongside plans to cut 14% of Tango's workforce, end preclinical research and concentrate on more advanced prospects. Prendergast suggested investors may have misinterpreted that decision. The simultaneous announcements made the reaction harder to read as a judgment on the trial alone. Leerink Partners analyst Andrew Berens pointed to additional pressures: other ESMO presentations suggested greater competition for Tango's type of drug, while questions about its relationship with Revolution also weighed on shares. Xencor's efficacy signal brings safety into focus. Xencor's early-stage kidney cancer treatment, XmAb819, drew a better reception. At the highest tested dose, the double-barreled antibody produced a 46% response rate in patients whose disease had progressed despite several previous treatments. RBC Capital Markets analyst Leonid Timashev said the efficacy surpassed expectations and looked stronger than results for other drugs studied in heavily treated patients. Leerink's Daina Graybosch reported that many investors viewed the presentation as among the meeting's strongest, while identifying side effects as a potential constraint. Xencor plans a Phase 3 trial in patients receiving their third treatment, comparing XmAb819 with Aveo Oncology's Fotivda. That planned comparison shifts attention from the encouraging early signal toward testing the drug against an existing treatment. The latest session was distinct from the conference reaction. At the Oct. 30, 2026 close, Moderna finished down 0.47%, Tango gained 0.84% and Xencor rose 2.09%. Those daily moves should not be mistaken for their returns across the meeting.

Merck shares rose more than 2% on Friday, a day after the pharmaceutical company posted strong third-quarter results. The S&P 500 fell 1.8% over the same session. Total sales grew 5% to over $18 billion, driven by its cancer drug Keytruda. Adjusted net income fell 4% to nearly $6.2 billion. Both figures beat average analyst estimates, as did its guidance for 2026. Several analysts raised their price targets. Jason Gerberry of Bank of America Securities lifted his to $165 from $163, while Chris Schott of J.P. Morgan raised his to $175 from $165. Both kept buy-equivalent ratings. Merck's dividend currently yields 2.3%.

Investors reacted sharply to cancer data at the European Society for Medical Oncology (ESMO) meeting, and good results did not always lift shares. Moderna's shares fell by double digits after it and Merck & Co. presented details on their personalised cancer vaccine, intismeran autogene. Investors want more data on other tumour types and on the commercial outlook for a vaccine made through a complex, personalised process. Tango Therapeutics fell about 20% despite an 82% response rate for its pancreatic cancer drug combination. It also announced plans to lay off 14% of its workforce, and analysts cited rising competition. Xencor was a top winner. Its kidney cancer antibody, XmAb819, showed a 46% response rate at the highest dose tested.