SLS, IBRX, IOVA End October In Red: Merck And AstraZeneca Earnings Put Cancer Bets And Buyout Hopes In Focus

AstraZeneca emphasized ADC combinations, cell therapies and internally developed cancer vaccines as key oncology priorities.

• Merck highlighted its Moderna-partnered cancer vaccine and new lung-cancer combinations.
• Sellas’s Phase 3 Regal trial reached 80 deaths, triggering final analysis, with preliminary GPS results expected this quarter.
• ImmunityBio secured expanded Anktiva approval and expects November trial results that could support treatment earlier in bladder cancer.

Sellas Life Sciences (SLS), ImmunityBio (IBRX) and Iovance Biotherapeutics (IOVA) ended October lower, while earnings updates from Merck (MRK) and AstraZeneca (AZN) put cancer vaccines, emerging competition and retail buyout hopes in focus.

IOVA plunged 43% in October, while SLS shed 21% and IBRX fell 12%, all sharply underperforming the SPDR S&P Biotech ETF (XBI), which slipped 1.1%.

Merck And AstraZeneca Map Their Cancer Push

Merck’s earnings call offered cancer-vaccine optimism alongside signs of growing competition in lung and bladder cancer. While discussing its Moderna-partnered melanoma vaccine, research chief Dean Li said: “These results, building on the body of evidence from the phase IIb study, strengthen our confidence in the curative potential of intismeran when given in combination with KEYTRUDA.”

Merck also highlighted a Keytruda-ADC combination that improved progression-free survival over Keytruda plus chemotherapy in a first-line lung-cancer study, and Phase 2 vaccine trials in bladder cancer. These programs point to potential future competition in markets targeted by Iovance and ImmunityBio.

On AstraZeneca’s call, CEO Pascal Soriot highlighted its Summit Therapeutics partnership combining antibody-drug conjugates, or ADCs, with Ivonescimab. 

“We believe ADCs will become the backbone of treatment across tumor types, and this partnership gives flexibility to combine them with the optimal next-generation immuno-oncology partner for each setting,” he said. AstraZeneca is also investing in cell therapies and developing cancer vaccines internally.

Merck’s dealmaking outlook offered another opening for retail buyout hopes. “Business development remains an important priority, and we retain financial flexibility within a strong investment-grade credit rating to pursue additional science-driven value-enhancing transactions,” CFO Caroline Litchfield said.

SLS, IBRX, IOVA: Key Cancer Readouts Draw Closer

Sellas is nearing a key readout after its Phase 3 Regal trial reached 80 deaths last week, triggering final analysis. Results for WT1-targeting GPS in acute myeloid leukemia (AML) patients in second remission are expected this quarter. Its pipeline also includes CDK9 inhibitor SLS009.

ImmunityBio’s Anktiva plus BCG also gained expanded FDA approval last month for BCG-unresponsive non-muscle-invasive bladder cancer, including papillary-only disease. Upcoming results from a 366-patient trial could support expansion into BCG-naive disease, where AstraZeneca’s Imfinzi already competes. A filing is targeted for the fourth quarter.

Iovance is pursuing lung cancer beyond Amtagvi’s melanoma market. Its recent update showed a 24.6% response rate in 69 previously treated lung-cancer patients, with two responses awaiting confirmation. A retrospective subgroup of 22 current or former smokers with KRAS and HER2 wild-type tumors showed a 59.1% response rate.

Prospective testing through Positility starts in November. The frontline Optilism trial and a filing based on the broader lung-cancer cohorts are planned for 2027.

SLS, IBRX, IOVA Retail Looks Beyond October’s Losses

On Stocktwits, SLS and IOVA drew ‘extremely bullish’ sentiment with ‘high’ and ‘extremely high’ message volume, respectively, while IBRX lagged with ‘bearish’ sentiment and ‘low’ volume.

One user on SLS said: “Merck’s R&D chief Dean Li called the Moderna-partnered melanoma vaccine trial ‘a landmark study’ and hopes it becomes a standard of care.” The poster argued that GPS could eventually have broader applications in blood cancers.

Another user on IOVA said: “If I were the CEO of a potential buyer (MRK, BMY, AZN etc) I would use this IOVA stock drop and sentiment purge to start a discussion with Wayne if I had not already done so (I would have already done so).” The reference was to Iovance director Wayne Rothbaum. Another investor linked Merck’s 2027 investment outlook to their conviction that it would eventually buy Iovance.

A separate user on IBRX said: “If Merck ever Needed to make a move it is now.” The poster floated a $25 billion acquisition, framing Anktiva as a potential answer to future Keytruda revenue pressure.

The smaller biotechs have delivered the biggest year-to-date gains, with IBRX surging 319%, IOVA climbing 211% and SLS rising 157%, far outpacing MRK’s 45% gain and AMZN’s 8% advance.

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