Pfizer, Merck, Amgen Double Down On Cancer And Send Takeover Buzz Around SLS And IBRX Into Overdrive

IBRX and SLS align with Big Pharma’s cancer push, fueling retail partnership and buyout speculation.

• Pfizer’s Seagen portfolio grew 21%, while Padcev-Keytruda cut the risk of death by 35% in a bladder-cancer study.
• IBRX’s Anktiva revenue jumped 92% to $50.7 million as the company pursued a broader U.S. bladder-cancer label.
• SLS nears its pivotal GPS analysis in AML, with 78 of the required 80 events recorded in the Regal trial.

Pfizer, Merck and Amgen outlined plans to expand their cancer portfolios as part of their earnings on Tuesday, fueling more speculative retail chatter around smaller oncology companies like Sellas Life Sciences (SLS) and ImmunityBio (IBRX).

Pfizer Targets Cancer Growth With Padcev

Pfizer called oncology “a clear area of strength,” with its legacy Seagen portfolio growing 21% in the U.S., excluding a year-earlier stocking benefit. Padcev, the centerpiece of Pfizer’s Seagen acquisition, recently received an expanded approval with Merck’s Keytruda in muscle-invasive bladder cancer. The Phase 3 study showed a 35% reduction in the risk of death, leading Pfizer to call the combination potentially “practice-changing” for more than 42,000 U.S. patients.

Pfizer is now testing whether Padcev could help some patients avoid bladder-removal surgery. “Those patients will not have to go through this horrible operation,” CEO Albert Bourla said. “That would be really a big deal.”

The company is also developing more antibody-drug conjugates (ADCs), which deliver cancer-killing drugs directly to tumor cells, and a dual-action antibody to help the immune system attack cancer while restricting the tumor’s blood supply. “We aim to cement Pfizer as a leading developer of ADCs,” research chief Chris Boshoff said. 

Merck And Amgen Advance New Cancer Platforms

Merck, meanwhile, is preparing for life beyond Keytruda, which generated $8.4 billion in quarterly sales, up 4%. CEO Rob Davis called the drug’s coming loss-of-exclusivity period “more of a hill than a cliff,” predicting “a shallow dip with a fast return back to growth.”

A key part of the transition is sac-TMT, an ADC to deliver cancer-killing medicine directly to tumor cells carrying a protein called Trop-2. The drug helped certain endometrial-cancer patients live longer and delayed their disease from worsening compared with chemotherapy. Merck is testing it in 17 Phase 3 trials across several cancers. “We think it’s a cornerstone ADC,” research chief Dean Li said, calling sac-TMT “next-gen chemo.” He also said the drug could lead Merck to “rethink KEYNOTE-189,” its established Keytruda-plus-chemotherapy approach in lung cancer.

On the other hand, Amgen is pursuing the same survival-focused strategy with T-cell engagers, which help immune cells recognize and attack cancer cells. Its innovative-oncology portfolio grew 18% to about $2 billion, while sales of its lung-cancer drug Imdelltra more than doubled to $288 million. “Too many patients are still being treated with chemotherapies that do not offer the survival benefit demonstrated by IMDELLTRA,” commercial chief Murdo Gordon said.

Amgen is now testing Imdelltra in earlier-stage small-cell lung cancer and advancing Xaluritamig through two Phase 3 prostate-cancer studies.

IBRX And SLS Fit Big Pharma’s Cancer Push 

ImmunityBio’s Anktiva aligns with Big Pharma’s push toward bladder-preserving, immune-based cancer treatments. Approved with BCG for certain bladder-cancer patients, it activates immune cells and may help some avoid bladder removal.

“For patients with BCG-unresponsive bladder cancer, the choice has too often been between losing the bladder and running out of options,” founder Patrick Soon-Shiong said last month. In a papillary-only study, 58% of patients remained disease-free after one year and 83% avoided bladder removal at three years. The FDA is reviewing a label expansion, with a decision due by Jan. 6, 2027.

Anktiva recently secured broader UAE approval, while growing adoption lifted quarterly revenue 92% to a record $50.7 million.

Meanwhile, Sellas’ Phase 3 Regal trial is testing GPS as maintenance therapy for acute myeloid leukemia (AML). The study has recorded 78 of the 80 events needed for its final analysis. The trial would succeed if GPS extends median survival to 12.6 months from eight months under standard treatment. Sellas is also testing SLS009 in newly diagnosed, high-risk AML patients. The company ended June with an estimated $138.3 million in cash. 

How Do Retail Traders Feel About IBRX And SLS?

On Stocktwits, retail sentiment was ‘bullish’ for IBRX amid ‘high’ message volume, while SLS sentiment remained ‘neutral’ amid ‘normal’ levels of chatter.

“Don’t underestimate the desperation a patent cliff creates in Big Pharma,” one trader said, citing the revenue gap Merck could face after Keytruda loses exclusivity. “Acquisitions in this space is not if but when and who.”

Another user predicted that GPS and SLS009 would generate billions of dollars in sales over the next decade, arguing that Big Pharma companies facing a “patent cliff apocalypse” would need to secure new assets.

An IBRX trader speculated that the stock could fall to $1 before “some Big Pharma” stepped in to acquire the company. A third user favored a potential J&J deal, citing its strong balance sheet and cancer ambitions, but argued that Merck might have more at stake, and therefore more incentive to bid, if another company acquired SLS and its GPS and SLS009 programs.

While SLS stock has surged 643% over the past year, IBRX stock is up 189% over the same period. 

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