7 Upcoming FDA Decisions in Q2 2026 to Watch

The second quarter of 2026 stands as a pivotal window for the oncology and hematology sectors, with several high-stakes FDA decisions poised to reshape the treatment landscape for complex malignancies. From novel antibody-drug conjugates to cutting-edge allogeneic T-cell immunotherapies, the upcoming regulatory rulings reflect a continued push toward precision medicine and improved survival outcomes for patients with limited options.

Here, we highlight the most anticipated FDA decisions expected in Q2 2026. As we move deeper into the year, these decisions represent potential new standards of care for patients facing aggressive disease.

Dato-DXd in Triple-Negative Breast Cancer

Expected Q2

The FDA granted priority review to datopotamab deruxtecan (Dato-DXd; Datroway) for the treatment of adult patients with unresectable or metastatic triple-negative breast cancer (TNBC) who are not eligible for PD-L1 or PD-1 inhibitor therapy in February 2026. While a specific target action date was not provided, AstraZeneca, the sponsor, indicated that the decision would be expected in Q2.¹

The application was supported by the pivotal phase 3 TROPION-Breast02 clinical trial (NCT05374512), which evaluated the efficacy and safety of Dato-DXd compared with the investigator’s choice of chemotherapy in the first-line setting. Analysis revealed a median overall survival (OS) of 23.7 months for patients receiving the antibody-drug conjugate compared with 18.7 months for those in the chemotherapy cohort (HR, 0.79; 95% CI, 0.64-0.98; P =.0291). This 5.0-month improvement represents a landmark in the management of metastatic TNBC, a subtype historically characterized by poor prognosis and limited therapeutic options.

RP1 in Melanoma

Expected April 10

In July 2025, Replimune Group, the sponsor, received a complete response letter (CRL) from the FDA regarding its biologics license application (BLA) for RP1 (vusolimogene oderparepvec), an oncolytic immunotherapy, in combination with nivolumab (Opdivo) for the treatment of advanced melanoma.³

The FDA indicated that it was unable to approve the BLA, primarily citing concerns that the pivotal IGNYTE trial (NCT03767348) was not considered an adequate and well-controlled clinical investigation to provide substantial evidence of effectiveness.

A type A meeting with the FDA followed in September 2025, from which a clear path forward had not been determined.⁴ Now, the BLA is up for consideration once more.

T-DXd Plus THP in HER2+ Breast Cancer

Expected May 18

Data from the phase 3 DESTINY-Breast11 study (NCT05113251) support the supplemental BLA of trastuzumab deruxtecan (T-DXd; Enhertu) followed by paclitaxel, trastuzumab (Herceptin), and pertuzumab (Perjeta; THP) for the neoadjuvant treatment of adult patients with HER2-positive stage 2 or 3 breast cancer.⁵

Findings presented at the 2025 ESMO Congress demonstrated that patients treated with T-DXd followed by THP (n = 321) experienced an improved pathologic complete response rate of 67.3% compared with 56.3% for those given doxorubicin and cyclophosphamide plus THP.

Sonrotoclax in R/R Mantle Cell Lymphoma

Expected May 26

In November 2025, the FDA granted priority review to the new drug application (NDA) of sonrotoclax (BGB-11417), an investigational, next-generation BCL2 inhibitor. It is indicated for the treatment of adult patients with relapsed or refractory mantle cell lymphoma following prior therapy with a BTK inhibitor.⁶

The FDA acceptance of the NDA for sonrotoclax marks a significant regulatory acceleration, indicating the potential for this agent to offer a substantial improvement in the safety or effectiveness of treatment for this serious, high-unmet-need condition.

Vepdegestrant in ESR1-Mutant Breast Cancer

Expected June 5

The NDA for vepdegestrant, an investigational oral PROteolysis TArgeting Chimera (PROTAC), seeks approval for the agent as a monotherapy in patients with estrogen receptor-positive (ER+), HER2-negative (HER2–), ESR1-mutated advanced or metastatic breast cancer who have progressed on prior endocrine-based therapy.⁷ This development marks a significant step forward in providing a new, targeted treatment option for a patient population that often faces limited therapeutic choices after first-line treatment.

Ga 68 Edotreotide in PET Imaging for NETs

Expected June 29

Ga 68 edotreotide (LNTH-2501) is a diagnostic radiopharmaceutical kit designed to support PET imaging and enables the preparation of the imaging agent used to detect SSTR-positive neuroendocrine tumors (NETs). The target action date for Ga 68 edotreotide was originally slated for March 29, but the deadline was extended to June 29 to give the FDA more time to review manufacturing-related information submitted as part of the application.⁸

Orca-T in Hematologic Malignancies

Originally expected April 6; now expected July 6

Orca-T, an investigational allogeneic T-cell immunotherapy, is being considered for the treatment of hematologic malignancies including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and myelodysplastic syndromes (MDS).

The phase 3 Precision-T study met its primary end point of survival free of chronic GVHD (cGVHD). In the Orca-T arm, 78% (95% CI, 65%-87%) of patients achieved survival free of cGVHD compared with 38% (95% CI, 73%-90%) in patients who underwent allogeneic hematopoietic stem cell transplant (alloHSCT).

As of March 2025, an interim analysis of the secondary end point of OS showed that OS was 94% (95% CI, 86%-97%) in the Orca-T arm vs 83% (95% CI, 73%-90%) in the alloHSCT arm (HR, 0.49; P =.11823). The rates of cumulative incidence of moderate to severe cGVHD were 13% (95% CI, 5%-23%) in the Orca-T arm vs 44% (95% CI, 31%-56%) in the alloHSCT arm (HR, 0.19; P <.00002).

On April 1, 2026, Orca Bio, the sponsor, announced that the FDA extended the review period by 3 months to account for the submission of updated chemistry, manufacturing and controls information.⁹

REFERENCES

1. Datroway granted priority review in the US as 1st-line treatment for patients with metastatic triple-negative breast cancer who are not candidates for immunotherapy. News release. AstraZeneca. February 3, 2026. Accessed March 30, 2026. https://tinyurl.com/48fyu5tt

2. Orca Bio announces FDA acceptance and priority review of the biologics license application (BLA) for Orca-T to treat hematological malignancies. News release. Orca Bio. October 6, 2025. Accessed March 30, 2026. https://tinyurl.com/mpkppnky

3. Replimune receives complete response letter from fda for rp1 biologics license application. News release. Replimune Group, Inc. July 22, 2025. Accessed March 30, 2026. https://tinyurl.com/2x2zvr58

4. Replimune provides update following Type A meeting with FDA. News release. Replimune. September 18, 2025. Accessed March 30, 2026. https://tinyurl.com/cz7xf4eb

5. Harbeck N, Modi S, Pusztai L, et al. DESTINY-Breast11: neoadjuvant trastuzumab deruxtecan alone (T-DXd) or followed by paclitaxel + trastuzumab + pertuzumab (T-DXd-THP) vs SOC for high-risk HER2+ early breast cancer (eBC). Presented at: 2025 ESMO Congress; October 17-21, 2025; Berlin, Germany. Abstract 291O.

6. U.S. FDA grants priority review to sonrotoclax for the treatment of relapsed or refractory mantle cell lymphoma. News release. BeOne Medicines. November 26, 2025. Accessed March 31, 2026. https://tinyurl.com/vwfhr8sc

7. FDA gives Arvinas and Pfizer’s vepdegestrant NDA for breast cancer. News release. Pharmaceutical Technology. August 11, 2025. Accessed March 31, 2026. https://tinyurl.com/yc7v9yfj

8. Lantheus announces three-month extension of PDUFA date for LNTH-2501 (Ga 68 edotreotide), a PET diagnostic imaging kit targeting somatostatin receptor-positive (SSTR+) neuroendocrine tumors (NETs). News release. Lantheus Holdings, Inc. March 17, 2026. Accessed March 31, 2026. https://tinyurl.com/596vnanf

9. Orca Bio Announces FDA Review Extension of BLA for Orca-T for the Treatment of Hematologic Malignancies. News release. Orca Bio. April 1, 2026. Accessed April 1, 2026. https://tinyurl.com/pzak3p8w