India Approves Enhertu for Early-Stage HER2-Positive Breast Cancer Before Surgery: A New Paradigm in Pre-Operative Oncology

NEW DELHI — In a major expansion of targeted cancer therapies in South Asia, India’s drug regulator, the Central Drugs Standard Control Organisation (CDSCO), granted market permission on July 27, 2026, to AstraZeneca Pharma India Limited for Enhertu (trastuzumab deruxtecan). The clearance permits the drug’s use as a neoadjuvant treatment—given prior to surgery—in adult patients diagnosed with early-stage, HER2-positive Stage II or Stage III breast cancer.

The decision allows clinicians across India to incorporate this potent antibody–drug conjugate (ADC) into upfront treatment protocols, opening new avenues for tumor shrinkage (downstaging) and significantly boosting the potential for breast-conserving surgeries rather than full mastectomies.

What the Clearance Entails: Upfront Targeted Precision

The updated label approved by CDSCO covers Enhertu (100 mg/5 mL) administered as an initial systemic regimen, followed by standard chemotherapy and targeted agents comprising taxane, trastuzumab, and pertuzumab (collectively known as THP).

Eligibility hinges on precise diagnostic testing. Patients must demonstrate HER2-positive status either through immunohistochemistry (IHC 3+) or in situ hybridization (ISH+). In practice, this means individuals presenting with locally advanced, non-metastatic tumors can receive targeted precision therapy before an oncologist ever makes a surgical incision.

“Delivering advanced biological agents before surgery allows us to test the tumor’s real-time vulnerability,” notes Dr. Aris Thorne, a senior surgical oncologist not affiliated with the regulatory filing. “When we shrink a locally advanced mass upfront, we convert complex, high-mutilation surgeries into manageable, breast-conserving procedures while simultaneously neutralizing microscopic disease.”

The Science of Neoadjuvant ADCs: How Enhertu Works

Neoadjuvant therapy refers to medical treatments administered as a first step to shrink a tumor before the primary intervention, usually surgery. In HER2-positive breast cancer—an aggressive subtype marked by an overabundance of the human epidermal growth factor receptor 2 protein—traditional treatment relies on combining standard chemotherapy with HER2-targeted monoclonal antibodies.

Enhertu operates as a “guided missile” in biological therapy:

• Targeting Mechanism: The antibody component (trastuzumab) homes in specifically on the HER2 proteins studded across the surface of malignant cells.

• Payload Delivery: Once bound, the cell internalizes the compound, which releases a potent topoisomerase I inhibitor payload directly inside the cell.

• Bystander Effect: The payload permeates neighboring cancer cells, killing surrounding malignant tissue even if individual adjacent cells express lower levels of HER2.

Supporting Evidence: Global Trials and Regulatory Alignment

The CDSCO’s decision aligns India with global oncology trends moving ADCs into earlier, curable stages of disease. This regulatory momentum relies heavily on data from major clinical trials, including the pivotal Phase III DESTINY-Breast09 study.

This international momentum saw the U.S. Food and Drug Administration (FDA) approve two early-stage indications for fam-trastuzumab deruxtecan-nxki in May 2026: one for neoadjuvant care followed by THP, and another as adjuvant therapy for patients with residual invasive disease post-surgery. European regulatory bodies have similarly expanded indications, confirming a shift toward earlier ADC intervention.

Critical Safety Considerations: Monitoring Interstitial Lung Disease

While the therapeutic efficacy of trastuzumab deruxtecan is well documented, health experts emphasize that clinical administration demands strict monitoring for treatment-related toxicities. Common side effects include:

• Gastrointestinal distress (nausea, vomiting)

• Severe fatigue and lethargy

• Hematologic toxicities (neutropenia and low blood counts)

The most notable class-specific risk associated with Enhertu is Interstitial Lung Disease (ILD) / pneumonitis, observed in approximately 12% of patients in clinical trials. While most instances are low-grade, ILD can prove fatal if left unrecognized.

Clinical Safety Protocol: Indian prescribing guidelines require baseline high-resolution CT scans and periodic lung evaluations. Patients experiencing new or worsening respiratory symptoms (cough, fever, dyspnea) must undergo immediate clinical evaluation, prompt drug interruption, and systemic corticosteroid management if ILD is diagnosed.

Public Health Impact for India

Breast cancer remains the most frequently diagnosed malignancy among Indian women. HER2-positive tumors account for approximately 20% to 25% of all cases nationwide, though exact rates vary by region and diagnostic infrastructure.

Because a significant proportion of Indian women present with late-stage or locally advanced tumors at initial diagnosis, access to effective neoadjuvant therapies carries substantial public health weight:

1. Downstaging Large Tumors: Shrinking extensive primary lesions makes previously inoperable tumors operable.

2. Improving Surgical Outcomes: Increases the percentage of women eligible for breast-conserving surgery (lumpectomy) over complete radical mastectomy.

3. Evaluating Pathologic Response: Allows oncologists to assess how well the tumor responds in real time, guiding post-surgical maintenance strategies.

Challenges to Widespread Adoption

Despite regulatory approval, oncologists point out several real-world hurdles before Enhertu becomes standard care across all Indian clinical centers:

• Diagnostic Consistency: Accurate HER2 testing requires high-quality immunohistochemistry and FISH testing, which can vary outside tier-one tertiary hospitals.

• Socioeconomic & Cost Barriers: High-cost biological therapies often remain out of reach for non-insured populations, highlighting the need for patient assistance programs.

• Infusion & Safety Infrastructure: Managing potential toxicities like ILD necessitates specialized multidisciplinary teams, including pulmonologists and critical care specialists.

Summary for Patients and Families

For individuals facing a new diagnosis of Stage II or Stage III HER2-positive breast cancer, this CDSCO clearance means Indian oncologists now have an additional, internationally validated tool to shrink tumors before surgery.

Treatment decisions, however, remain deeply personal. Patients should consult their care team to discuss tumor stage, cardiac health, baseline lung function, and financial logistics to determine if pre-operative ADC therapy represents the right path forward.

Medical Disclaimer

This article is for informational purposes only and should not be considered medical advice. Always consult with qualified healthcare professionals before making any health-related decisions or changes to your treatment plan. The information presented here is based on current research and expert opinions, which may evolve as new evidence emerges.

References

1. Indian Pharma Post. “AstraZeneca gets CDSCO nod for expanded Enhertu indication in HER2-positive breast cancer.” Published July 28, 2026. https://www.indianpharmapost.com/drug-approval/astrazeneca-gets-cdsco-nod-for-expanded-enhertu-indication-in-her2-positive-breast-cancer