Oncology Overview: Atezolizumab (Tecentriq)

Atezolizumab (Tecentriq) is a monoclonal antibody indicated for treatment as a single or in-combination agent in 6 types of carcinomas in pediatric and adult populations. It initially gained accelerated approval in May 2016 for the treatment of locally advanced or metastatic urothelial carcinoma in patients who are unable to receive platinum-containing chemotherapy.^1,2

Atezolizumab works by blocking the programmed cell death ligand 1 (PD-L1) receptor pathway and became the first in its class to be approved.³ The latest approved indication came in July 2020 for the treatment of unresectable or advanced melanoma, in which atezolizumab works as part of triplet therapy.⁴

Mechanism of Action

Atezolizumab is an immunoglobulin that attaches to PD-L1 on tumor cells and blocks the PD-L1 receptor interactions.² This suppression allows activation of T-cell activity as part of the antitumor immune response.

Indications and Clinical Studies

Since its initial approval in 2016 for urothelial carcinoma, atezolizumab has received FDA approval for an additional 5 types of carcinomas. The indications and accompanying clinical trials are listed below.² 

• Locally advanced or metastatic urothelial carcinoma – IMvigor210
• Metastatic non-small cell lung cancer – IMpower110, IMpower150, IMpower130, OAK
• Metastatic triple-negative breast cancer – IMpassion130
• Extensive-stage small cell lung cancer – IMpower133
• Unresectable or metastatic hepatocellular carcinoma – IMbrave150
• Unresectable or metastatic melanoma – IMspire150

Confirmatory trials are ongoing for fast-tracked approved indications for urothelial carcinoma and triple-negative breast cancer.²

Dosage and Administration

For all indications, atezolizumab is administered intravenously as 840 mg every 2 weeks, 1200 mg every 3 weeks, or 1680 mg every 4 weeks. Clinicians administer the first infusion over 60 minutes, and if tolerated, shorten successive infusions to 30 minutes.² Treatment duration continues until toxicity or cancer progression occurs.

Adverse Events (AEs) and Warnings

When used as a sole agent, the most common AEs occurred in 20% or more of trial patients and include fatigue, cough, dyspnea, nausea, and decreased appetite.⁵ Risk of fertility impairment in female patients is also high.⁴

Less than 5% of patients exhibited severe AEs from infusion-related and immune-mediated responses (pneumonitis, hepatitis, colitis, myocarditis, nephritis, endocrinopathies, and dermatologic) when they received atezolizumab as a single agent.² Dose adjustments such as slowing infusion rate, withholding therapy, and/or discontinuation of therapy may be necessary in these cases.²

Before starting treatment, providers should evaluate pregnancy status in female patients. In pregnant patients, atezolizumab has the potential to cause fetal harm, including fetal loss.

Current data on excretion in human milk are unavailable. Female patients should use contraceptives and stop breastfeeding for the duration of atezolizumab treatment and for at least 5 months after receiving the final dose.² 

About the Author

Emilia Welch, PharmD, is a community pharmacist at East Main Pharmacy in Waterbury, Connecticut.

References

1. Atezolizumab for Urothelial Carcinoma. U.S. Food & Drug Administration website. https://www.fda.gov/drugs/resources-information-approved-drugs/atezolizumab-urothelial-carcinoma. Published online May 19, 2016. Accessed July 19, 2021.
2. Tecentriq [package insert]. South San Francisco, CA: Genentech, Inc; 2021.
3. FDA Approves New, Targeted Treatment for Bladder Cancer. U.S. Food & Drug Administration website. https://www.fda.gov/news-events/press-announcements/fda-approves-new-targeted-treatment-bladder-cancer. Published online May 18, 2016. Accessed July 19, 2021.
4. FDA Approves Atezolizumab for BRAF V600 Unresectable or Metastatic Melanoma. U.S. Food & Drug Administration website. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-atezolizumab-braf-v600-unresectable-or-metastatic-melanoma. Published online July 31, 2020. Accessed July 19, 2021.
5. Tecentriq (atezolizumab) HCP: Efficacy, Safety, PI & MOA. Tecentriq. https://www.tecentriq-hcp.com. Accessed July 19, 2021.