Oncology FDA approvals push immunotherapy into early-stage cancer

A month that redrew several cancer treatment pathways

October 2026 has been one of the busiest months this year for cancer drug regulation. It also has a clear theme. Across several tumor types, the FDA moved established drugs into earlier lines of therapy. It tied eligibility to specific biomarker tests, and in one notable case it narrowed an older label after the confirmatory evidence fell short. Together, the approvals show where oncology is heading: toward immunotherapy and targeted agents given earlier, to patients selected more carefully.

The month's most closely watched decision came on October 19. That day the agency granted accelerated approval to GSK's PD-1 inhibitor dostarlimab (Jemperli) for adults with stage II/III locally advanced rectal cancer that is microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR), with eligibility confirmed by an FDA-authorized test.12 Eleven days earlier, on October 8, the FDA approved Genentech's atezolizumab (Tecentriq) with fluoropyrimidine and oxaliplatin chemotherapy as adjuvant treatment for stage III dMMR colon cancer. That approval covered both the intravenous drug and the subcutaneous Tecentriq Hybreza.11 In between came a quieter but important change to Merck's pembrolizumab (Keytruda) label, and early in the month Eli Lilly's pirtobrutinib (Jaypirca) moved into frontline chronic lymphocytic leukemia.2131

Dostarlimab: replacing the standard treatment sequence

The dostarlimab approval is the most consequential of the group because of what it could let patients avoid. GSK says it is the first and only immunotherapy approved for this rectal cancer indication, which covers roughly 5% to 10% of rectal tumors.1318 Standard care for these patients has long meant chemotherapy, radiation and surgery, and the surgery can leave patients with a permanent colostomy.20

The approval rests on AZUR-1, a single-arm, open-label trial of 154 previously untreated patients. Each received 500 mg of dostarlimab intravenously every three weeks for nine cycles.12 Among 144 patients whose investigators could evaluate them, 68% had a clinical complete response sustained for 12 months, and the objective response rate was 82%.12 Of all 154 treated patients, 110 (71%) received dostarlimab alone with no further treatment and had no disease progression. Another 17% went on to surgery.14 In a detail that complicates the efficacy picture in a useful way, 12 of the 15 patients who had surgery because imaging suggested an incomplete response turned out to have a pathologic complete response.1418 Medscape also reported that no recurrences had been seen among responders after a median follow-up of more than two years.18

The FDA also reviewed supporting data from an investigator-led trial of 50 patients. In that study, 93% had a sustained 12-month clinical complete response and every patient responded.14 Memorial Sloan Kettering's Luis Diaz, one of the trial investigators, told TIME that the therapy had "leapfrogged" the standard of care. He said some patients who would have lost their fertility have since had children.20

The headline numbers are consistent across outlets, but they differ in emphasis. Trade publications stress that the approval is accelerated, not traditional. Medscape notes that continued approval may depend on a confirmatory trial.18 The ASCO Post points out that the primary endpoint was measured by independent central review, while the widely cited 68% figure comes from investigator assessment.1214 Consumer coverage focused more on the prospect of skipping surgery entirely.20 Both readings are fair, but the cautious one deserves weight. Single-arm data in a small biomarker group, with recurrence monitoring that continues for years, is a strong signal. It is not yet a settled standard of care.

The review process was also notable. The FDA cleared the application four months ahead of its goal date, using Real-Time Oncology Review, Project Orbis coordination with regulators in Canada, Israel, Switzerland and the UK, and the Commissioner's National Priority Review Voucher pilot.14 The same voucher program sped daraxonrasib through review for pancreatic cancer earlier this year.5 The pilot is clearly becoming a meaningful channel for high-profile oncology filings.

Atezolizumab in colon cancer: a randomized trial and a trade-off

The Tecentriq approval stands on firmer evidence. ATOMIC was a randomized, open-label phase 3 trial in patients with resected stage III dMMR colon cancer.11 Pharmaceutical Executive reported three-year disease-free survival of 86% with atezolizumab plus chemotherapy, compared with 76% for chemotherapy alone. It is the drug's 12th US indication.16 The added benefit has a cost in toxicity: grade 3–4 adverse events occurred in 84.1% of patients on the combination versus 71.9% on chemotherapy alone.16 The same publication noted that the five-year overall survival estimate has a wide confidence interval that includes no difference.16

The reports differ on small details. The FDA lists the approval date as October 8, while Roche's announcement and some trade coverage date it October 9.1116 The agency describes the trial as 711 adults plus one pediatric patient, and Roche rounds that to 712 patients.1116 None of this changes the substance. Commercially, the subcutaneous option matters. Roche says Tecentriq is now the first PD-1/PD-L1 immunotherapy available in both intravenous and subcutaneous forms for this setting. Adoption will also depend on routine mismatch repair testing.16

Keytruda's TMB label: an accelerated approval tightened

The pembrolizumab decision went in the other direction. On October 16, the FDA converted Keytruda's 2020 accelerated approval for tumor mutational burden-high (TMB-H) solid tumors to a traditional approval. In doing so it raised the threshold from at least 10 mutations per megabase to at least 13. The agency said efficacy was not confirmed for tumors in the 10-to-13 range.2124 The FDA announced the change publicly on October 22, which explains why some outlets date it to that day.2327

In 220 patients from the KEYNOTE-158 trial with TMB of at least 13, the objective response rate was 36%. Among responders, 58% kept their response for at least 12 months.25 An exploratory analysis of patients with TMB between 10 and 13 found a response rate of just 13%.24 Oncology Nursing News pointed out that the efficacy population mixes a prospectively enrolled cohort with a retrospective analysis, and that responses were not broken out by tumor type.24 CURE noted that some patients who qualified under the old definition will no longer qualify.26

This decision deserves more attention than it has received. It is a working example of the accelerated approval system correcting itself: the agency kept the indication but narrowed it to match the evidence. Coverage agrees on the facts. A University of Miami oncologist quoted by CancerNetwork presented it as evidence that biomarker cutoffs should be refined using clinical outcome data.27 Patient-facing materials published only weeks earlier still list 10 mutations per megabase as the cutoff, so clinicians and patients will have to recheck old test reports.3024

Pirtobrutinib and the steady shift away from chemotherapy

In blood cancers, the FDA on October 2 approved pirtobrutinib for adults with previously untreated CLL or small lymphocytic lymphoma with no known 17p deletion. Pirtobrutinib is the first and only approved non-covalent BTK inhibitor.3235 In the phase 3 BRUIN CLL-313 trial, which enrolled 282 patients, pirtobrutinib cut the risk of progression or death by about 80% compared with bendamustine plus rituximab (hazard ratio 0.20). Median progression-free survival had not been reached with pirtobrutinib, versus 33.5 months on chemoimmunotherapy.31 Overall survival data are still immature.38 One detail cuts against the headline response figures: complete responses were more common with bendamustine-rituximab (21%) than with pirtobrutinib (13%).31

Pirtobrutinib beat a chemoimmunotherapy regimen rather than one of the covalent BTK inhibitors already used first-line. Its real competitive position will therefore depend on the separate head-to-head BRUIN CLL-314 trial against ibrutinib.3237 One commentary called the approval part of a broader shift in CLL toward pathway-directed therapy and away from traditional chemoimmunotherapy.39

What the month adds up to

These decisions extend a busy year. Between January and June, oncology logged 22 FDA approvals across 19 distinct drugs.2 September brought 24 regulatory developments, including accelerated approvals in ESR1-mutant breast cancer and HER2-mutant lung cancer, as well as several refusals and delays.3 October has also included a tucatinib maintenance approval in HER2-positive breast cancer and several fast track and breakthrough designations.19

The clearest reading is that regulators are now comfortable approving immunotherapy in curative-intent, early-stage settings when a biomarker identifies patients likely to respond, and that testing has become a condition of treatment. Each of the month's three main solid-tumor decisions required an FDA-authorized or companion test.121621 The pembrolizumab revision shows the other side of that policy: when the confirmatory evidence does not support the original cutoff, the label shrinks. For patients with dMMR rectal or colon cancer, October marks a real change in options. The longer-term question is whether accelerated approvals like dostarlimab's hold up over years of follow-up, not just the 12 months of the current data.