Breast Cancer Treatments Awaiting FDA Decisions: 4 to Watch

Four breast cancer drug applications are under the Food and Drug Administration (FDA) review right now, and several more drugs are moving through late-stage trials. Here is where each stands as of early September, in order of when a decision is expected.

Giredestrant for Early-Stage ER-Positive Breast Cancer

Decision expected: Nov. 30, 2026

Giredestrant is an oral selective estrogen receptor degrader (SERD), a daily pill that blocks estrogen from attaching to its receptor and then breaks the receptor down. Oral SERDs are already approved for metastatic disease, but giredestrant would be the first approved for early-stage breast cancer, where the goal is preventing the cancer from returning.

The FDA granted priority review in June based on the phase 3 lidERA trial of more than 4,100 people with ER-positive, HER2-negative stage 1 to 3 breast cancer. Giredestrant reduced the risk of invasive disease returning or death by 30% compared with standard endocrine therapy. At three years, 92.4% of people taking giredestrant were alive without invasive disease versus 89.6% on standard care, and fewer stopped treatment because of side effects (5.3% versus 8.2%). Overall survival data are not yet mature but trend in giredestrant's favor.

What it means: Most people with early ER-positive breast cancer take an aromatase inhibitor or tamoxifen for five to 10 years, and side effects lead many to quit early. Roche's chief medical officer, Dr. Levi Garraway, called giredestrant "the first major endocrine therapy advance in early-stage ER-positive breast cancer in decades."

Giredestrant Plus Afinitor for ESR1-Mutated Metastatic Breast Cancer

Decision expected: Dec. 18, 2026

The same drug is under separate review, paired with Afinitor (everolimus), for ER-positive, HER2-negative, ESR1-mutated advanced breast cancer that has progressed after endocrine therapy and a CDK4/6 inhibitor.

In the phase 3 evERA trial, the combination extended progression-free survival to 9.99 months versus 5.45 months with standard care in people with ESR1 mutations, a 62% reduction in the risk of progression or death. Across all participants, the benefit was 8.77 months versus 5.49 months. Read more.

What it means: This is a chemotherapy-free option at a point where many people are running out of endocrine-based choices. Notably, no cases of photopsia (visual flashes), a side effect seen with some other SERDs, were reported.

Tukysa as Maintenance for HER2-Positive Metastatic Breast Cancer

Decision expected: 2026, per Pfizer; no date announced

Tukysa (tucatinib) is already approved for later lines of HER2-positive breast cancer. The new application, based on the phase 3 HER2CLIMB-05 trial, would move it up to first-line maintenance, given with Herceptin (trastuzumab) and Perjeta (pertuzumab) after initial chemotherapy.

Adding Tukysa extended median progression-free survival from 16.3 months to 24.9 months, an 8.6-month improvement and a 36% reduction in the risk of progression or death. Only 6% of participants stopped Tukysa because of side effects, most often elevated liver enzymes, and an exploratory analysis found progression-free survival nearly doubled in people with brain metastases. Read more.

What it means: "Patients conceivably can drop out their cytotoxic chemo and be on targeted therapy only," said Dr. Erika Hamilton, who presented the data. Pfizer lists the FDA decision among its anticipated 2026 milestones but has not disclosed a target date.

Camizestrant for Emerging ESR1 Mutations

Decision expected: Delayed; no new date assigned

Camizestrant, another oral SERD, is under review for a different strategy: switching people with HR-positive, HER2-negative metastatic breast cancer from an aromatase inhibitor to camizestrant the moment a blood test detects an ESR1 mutation, before scans show the cancer growing. In the phase 3 SERENA-6 trial, the early switch extended progression-free survival to 16 months versus 9.2 months.

The path has been rocky. In April, the FDA's Oncologic Drugs Advisory Committee voted 6-3 against a favorable benefit-risk profile for camizestrant in this setting. In May, the FDA extended its review to evaluate additional data, and AstraZeneca has said regulators have not yet set a new decision date. European regulators, meanwhile, issued a positive opinion in May.

What it means: This is as much a decision about strategy as about a drug. If approved, it would be the first FDA-approved breast cancer treatment strategy that changes therapy based on an ESR1 mutation detected in circulating tumor DNA before scans show the disease progressing.

Further Back in the Pipeline

Several drugs have earned FDA designations that speed development but are still in trials. Zovegalisib, a PI3Kα inhibitor designed to hit only the mutant protein and spare healthy cells, received breakthrough therapy designation in February for PIK3CA-mutated, HR-positive, HER2-negative advanced disease and is in the phase 3 ReDiscover-2 trial. Atirmociclib, a next-generation CDK4 inhibitor from Pfizer, cut progression risk by 40% in a phase 2 trial and is now in phase 3 testing as a first-line treatment. ART6043, paired with Lynparza (olaparib) for BRCA-mutated disease, and TER-2013, an AKT1 inhibitor, both hold fast track designation but remain in early-phase trials.

What the FDA Has Approved in 2026

For readers catching up, the FDA's six breast cancer decisions this year covered Veppanu (vepdegestrant) and Revtorpyk (gedatolisib) for HR-positive metastatic disease, Enhertu for HER2-positive early-stage disease, Datroway and Trodelvy for certain people with metastatic triple-negative breast cancer, and Ibrance (palbociclib) as maintenance therapy for HR-positive, HER2-positive advanced disease.

If any of the pending treatments matches your diagnosis, ask your oncologist whether a clinical trial is enrolling near you, and watch CURE for coverage when the FDA decides.

References

1. Roche. FDA accepts New Drug Application for Roche's giredestrant in ER-positive early-stage breast cancer. June 2, 2026. https://www.roche.com/media/releases/med-cor-2026-06-02
2. Roche. FDA accepts New Drug Application for Roche's giredestrant in ESR1-mutated, ER-positive advanced breast cancer. Feb. 20, 2026. https://www.roche.com/media/releases/med-cor-2026-02-20
3. Pfizer. TUKYSA added to first-line maintenance therapy extends median progression-free survival by over 8 months in patients with HER2+ metastatic breast cancer. https://www.pfizer.com/news/press-release/press-release-detail/tukysa-added-first-line-maintenance-therapy-extends-median
4. AstraZeneca. Update on FDA Advisory Committee vote on camizestrant in combination with a CDK4/6 inhibitor for advanced HR-positive breast cancer. April 30, 2026. https://www.astrazeneca.com/media-centre/press-releases/2026/fda-odac-vote-on-camizestrant-breast-cancer.html
5. AstraZeneca. US FDA decision date extended for SERENA-6 filing of camizestrant to enable review of additional data. May 27, 2026. https://www.astrazeneca.com/media-centre/press-releases/2026/us-fda-decision-date-camizestrant-extended.html
6. Pfizer. Pfizer announces positive topline phase 2 results for next-generation CDK4 inhibitor, atirmociclib, in second-line metastatic breast cancer. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-announces-positive-topline-phase-2-results-next

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