This Week in Oncology: FDA Approval Shakeups and Key SITC 2025 Data

This week, the FDA approved an interchangeable biosimilar formulation of pertuzumab known as pertuzumab-dpzb, a HER2-neu receptor agonist, in different breast cancer populations.

This November has already provided many exciting developments across the multidisciplinary oncology world. Within the first half of the month alone, the FDA has been busy issuing new approvals and regulatory nods across different breast cancer, leukemia, and gynecologic malignancy populations. Additionally, presentations from the recent 2025 Society for Immunotherapy of Cancer Annual Meeting showcased novel treatment modalities that may show utility across various treatment settings.

CancerNetwork® reported on these latest potential shakeups across oncology. Here are the top 5 takeaways of the week that may influence the future of the field.

#1: FDA Approves Pertuzumab Biosimilar in Breast Cancer Indications

The FDA approved an interchangeable biosimilar formulation of pertuzumab (Perjeta) known as pertuzumab-dpzb (Poherdy), a HER2-neu receptor agonist, in different breast cancer populations.1

Based on various comparisons of parameters related to safety and efficacy, pharmacokinetic data, clinical immunogenicity findings, and supportive clinical data, the agency determined that the biosimilar exhibited sufficient similarity to the reference product. The biosimilar is indicated for use in combination with agents like trastuzumab (Herceptin) across different treatment settings, including adults with HER2-positive metastatic breast cancer who have not received prior anti-HER2 treatment or chemotherapy for metastatic disease.

#2: FDA Approves Ziftomenib in R/R NPM1-Mutated Acute Myeloid Leukemia

Another key regulatory decision was the FDA’s approval of ziftomenib (Komzifti) for patients with relapsed/refractory acute myeloid leukemia (AML) harboring NPM1 mutations, based on data from the phase 1b/2 KOMET-001/KO-MEN-001 trial (NCT04067336).2

Topline results from the study showed that 21.4% (95% CI, 14.2%-30.2%) of evaluable patients achieved a complete response (CR) or CR with partial hematologic recovery. Additionally, in 66 patients with red blood cell and/or platelet transfusion dependence at baseline, transfusion independence at any 56-day post-baseline period occurred in 14 (21.2%).

#3: Mecbotamab Vedotin Shows Positive OS Results in Soft Tissue Sarcoma

Data presented at SITC 2025 showed that treatment with mecbotamab vedotin (Mec-V) elicited an overall survival (OS) benefit for those with treatment-refractory leiomyosarcoma, liposarcoma, or undifferentiated pleomorphic sarcoma in a phase 2 trial (NCT03425279).3

Across the overall population, the median OS was 18.4 months (95% CI, 7.2-not evaluable [NE]) with Mec-V alone and 22.9 months (95% CI, 14.2-NE) with Mec-V plus nivolumab (Opdivo). Across different subgroups, the median OS was 19.0 months (95% CI, 7.9-29.9) for patients with leiomyosarcoma, 21.7 months (95% CI, 3.7-NE) for those with liposarcoma, and 21.5 months (95% CI, 5.0-NE) for those with undifferentiated pleomorphic sarcoma.

#4: Novel T-Cell Therapies Yield Decade-Long Remission in Epithelial Cancer

In other presentations shared at SITC 2025, investigational cellular therapies demonstrated various benefits across different epithelial cancer populations.

Findings from one single-center phase 2 trial (NCT05686226) showed that T cell receptor (TCR)–T-cell therapy could produce responses in a small cohort of patients with metastatic HPV-associated cancers.4 Moreover, another presentation on a different phase 2 trial (NCT01585428) highlighted 2 patients with metastatic cervical cancer who remained in CR for at least 10 years following a single infusion of tumor-infiltrating lymphocyte therapy.5

#5: FDA Approves Diagnostic Tool for Pembrolizumab Combo in Endometrial Cancer

In another notable decision from the FDA, the agency approved the Promega OncoMate® MSI Dx Analysis System as a companion diagnostic for identifying patients with microsatellite-stable endometrial carcinoma who may benefit from treatment with pembrolizumab (Keytruda) in combination with lenvatinib (Lenvima).6

Previously, the agency approved pembrolizumab/lenvatinib for this endometrial carcinoma population in July 2021.7 This decision was based on findings from the phase 3 KEYNOTE-775 study (NCT03517449).

References

1. FDA approves new interchangeable biosimilar to Perjeta. News release. FDA. November 13, 2025. Accessed November 14, 2025. https://tinyurl.com/2vzwt6ej
2. FDA approves ziftomenib for relapsed or refractory acute myeloid leukemia with a NPM1 mutation. News release. FDA. November 13, 2025. Accessed November 14, 2025. https://tinyurl.com/2mcsxzuv
3. Druta M, Pollack SM, Conley AP, et al. Median OS of 21.5 months among 44 patients with treatment-refractory leiomyosarcoma, liposarcoma, and undifferentiated pleomorphic sarcoma treated with mecbotamab vedotin, an AXL-targeting ADC. Presented at the Society for Immunotherapy of Cancer (SITC) 2025 Annual Meeting; National Harbor, MD; November 5-9, 2025.
4. Norberg SM, Doran SL, Cao J, et al. Complete tumor regression of metastatic epithelial cancer following T cell receptor (TCR)-T cell therapy. Presented at the Society for Immunotherapy of Cancer (SITC) 2025 Annual Meeting; National Harbor, MD; November 5-9, 2025. Abstract 366.
5. Norberg SM, Biswas A, Krishnamurthy S, et al. Decade-long epithelial cancer remissions from cellular therapy. Presented at the Society for Immunotherapy of Cancer (SITC) 2025 Annual Meeting; National Harbor, MD; November 5-9, 2025. Abstract 377.
6. FDA approves Promega OncoMate MSI Dx Analysis System as companion diagnostic for KEYTRUDA in combination with LENVIMA in advanced endometrial carcinoma. News release. Promega. November 11, 2025. Accessed November 14, 2025. https://tinyurl.com/2jdnn7r7
7. FDA grants regular approval to pembrolizumab and lenvatinib for advanced endometrial carcinoma. FDA. July 21, 2021. Accessed November 14, 2025. https://tinyurl.com/49hzfsvh