What Is Sacituzumab Govitecan?

Sacituzumab Govitecan (marketed as Trodelvy) is an antibody-drug conjugate (ADC) that consists of an anti-Trop-2 antibody linked to SN-38, a topoisomerase I inhibitor. Trop-2 is a cell surface glycoprotein that is overexpressed in many epithelial cancers, making it an ideal target for directed therapy.

This medication was developed by Immunomedics, which was later acquired by Gilead Sciences. The FDA granted accelerated approval for Sacituzumab Govitecan in 2020 for treating adult patients with metastatic triple-negative breast cancer (TNBC) who have received at least two prior therapies. Since then, its indications have expanded to include hormone receptor-positive, HER2-negative metastatic breast cancer and certain cases of urothelial cancer.

How Sacituzumab Govitecan Works

The mechanism of action for Sacituzumab Govitecan involves multiple steps that make it particularly effective against cancer cells. First, the antibody component binds specifically to Trop-2 receptors on cancer cell surfaces. After binding, the entire complex is internalized into the cancer cell through endocytosis.

Once inside the cell, lysosomal enzymes cleave the linker between the antibody and SN-38, releasing the active drug within the cancer cell. SN-38 is a potent topoisomerase I inhibitor that prevents DNA repair in rapidly dividing cells, leading to DNA damage and ultimately cell death. This targeted approach allows for delivery of higher concentrations of the cytotoxic agent directly to cancer cells while minimizing exposure to healthy tissues.

Additionally, Sacituzumab Govitecan demonstrates a bystander effect, where the SN-38 can diffuse into nearby tumor cells even if they don't express Trop-2, potentially enhancing its overall efficacy against heterogeneous tumors.

Provider Comparison and Availability

Several pharmaceutical companies are involved in the development and distribution of antibody-drug conjugates similar to Sacituzumab Govitecan, though Trodelvy remains the only approved Trop-2 directed ADC for breast cancer.

Gilead Sciences, through its acquisition of Immunomedics, manufactures and distributes Trodelvy (Sacituzumab Govitecan) globally. The company provides patient support programs to help with access and financial assistance.

Daiichi Sankyo and AstraZeneca have partnered on several ADCs, including Enhertu (trastuzumab deruxtecan), which targets HER2-expressing cancers using a different mechanism.

Seagen (formerly Seattle Genetics) specializes in ADC technology and markets Padcev (enfortumab vedotin) for urothelial cancer, representing another approach to targeted cancer therapy.

Each provider offers different support services, distribution networks, and pricing structures, making it important for healthcare providers and patients to explore all options when considering treatment.

Benefits and Challenges of Sacituzumab Govitecan

Benefits:

  • Demonstrated efficacy in difficult-to-treat cancers like triple-negative breast cancer
  • Targeted approach that may reduce damage to healthy cells compared to traditional chemotherapy
  • Option for patients who have progressed after standard therapies
  • Convenient outpatient administration via intravenous infusion

Challenges:

  • Side effects include neutropenia, diarrhea, nausea, fatigue, and alopecia
  • Risk of severe neutropenia which requires careful monitoring
  • Potential for hypersensitivity reactions during infusion
  • Higher cost compared to conventional chemotherapy
  • Limited long-term data on durability of response

Research continues through clinical trials exploring Sacituzumab Govitecan in additional cancer types and in combination with other therapies, including immunotherapies like Keytruda (pembrolizumab) from Merck.

Treatment Considerations and Pricing

Sacituzumab Govitecan is administered as an intravenous infusion on days 1 and 8 of 21-day treatment cycles. The recommended dose is 10 mg/kg, with adjustments possible based on individual tolerance and response. Treatment typically continues until disease progression or unacceptable toxicity occurs.

Pricing for Sacituzumab Govitecan reflects its specialized nature as a targeted therapy. The wholesale acquisition cost can range from $2,000 to $2,500 per vial, with a typical treatment course requiring multiple vials depending on patient weight. A full course of treatment may cost between $100,000 to $300,000 annually before insurance coverage.

Insurance coverage varies significantly between providers. Most commercial insurance plans and Medicare cover Sacituzumab Govitecan for FDA-approved indications, though prior authorization is typically required. Gilead Sciences offers a patient support program through Trodelvy Access Services that can help navigate insurance issues and may provide financial assistance for eligible patients.

When considering this treatment, patients should discuss with their healthcare providers not only the potential benefits and risks but also practical aspects like treatment schedule, monitoring requirements, and financial implications.

Conclusion

Sacituzumab Govitecan represents an important advancement in precision oncology, offering new hope for patients with difficult-to-treat cancers. As research continues, its role in cancer treatment may expand to additional indications and combination strategies. Patients considering this therapy should work closely with their healthcare team to understand the potential benefits, risks, and practical considerations involved. With ongoing clinical trials and increasing real-world experience, our understanding of how to optimize treatment with this innovative antibody-drug conjugate continues to evolve. While challenges remain, including managing side effects and addressing cost concerns, Sacituzumab Govitecan has established itself as a valuable addition to the cancer treatment landscape.

Citations

This content was written by AI and reviewed by a human for quality and compliance.