Ursula A. Matulonis, MD, Reviews the Rationale Behind the SORAYA Trial of Mirvetuximab Soravtansine in Ovarian Cancer With High FR-α Expression

At the 2022 Annual Global Meeting of the International Gynecologic Cancer Society, CancerNetwork^® spoke with Ursula A. Matulonis, MD, chief of the Division of Gynecologic Oncology, Brock-Wilson Family Chair, and institute physician at Dana-Farber Cancer Institute as well as professor of medicine at Harvard Medical School in Boston, Massachusetts, about the reasoning behind the phase 3 SORAYA trial (NCT04296890), which investigated mirvetuximab soravtansine in patients with folate receptor (FR) α–high platinum-resistant ovarian cancer.¹

Transcript:

Women with advanced platinum-resistant ovarian cancer have very limited options. Most of them have received bevacizumab [Avastin] as part of their upfront or recurrence regimen. They have single-agent, non–platinum-based chemotherapy as options, and these range [in efficacy] from response rates of 4% up to 12% or 13%. The durations of response are quite short, and that’s measured in weeks. There has not been an FDA approval in the platinum-resistant setting since 2014.² The SOROYA study is a very positive trial and mirvetuximab soravtansine is a very active and promising agent.

Mirvetuximab soravtansine is an antibody-drug conjugate. It targets the folate receptor 1, or FR- α, which is present in around 35% to 40% of high-grade serous ovarian cancer. The antibody-drug conjugate is an antibody to FR-α and is linked to a toxin called DM4, which is a maytansinoids toxin. It’s an anti-microtubule drug and this drug has been in clinical testing for a number of years. SORAYA is a phase 3 study, although it’s not a randomized and it’s a single-arm trial. This is testing the effectiveness of mirvetuximab soravtansine as a single agent at a dose of 6 mg/kg using the ideal body weight in patients with platinum-resistant, high-grade serous ovarian cancer.

To get into the SORAYA study, patients had to have platinum-resistant, high-grade serous ovarian cancer and at least 1 and up to 3 prior lines of treatment. All patients had to receive prior bevacizumab and their cancer had to demonstrate FR- α with high membrane staining using the IHC PS [immunohistochemistry performance score] 2 scoring, meaning that 75% or higher of the cancer cells had to be positive for FR- α with 2 plus or higher staining intensity.

References

1. Coleman RL, Matulonis U, Lorusso D, et al. Clinical benefit of mirvetuximab soravtansine in ovarian cancer patients with high folate receptor alpha expression: results from the SORAYA study. Presented at: 2022 Annual Global Meeting of the International Gynecologic Cancer Society; New York, NY; September 29-October 1, 2022. Abstract O028.
2. FDA approves bevacizumab in combination with chemotherapy for platinum resistant, recurrent ovarian cancer. News Release. European Society for Medical Oncology. November 18, 2014. Accessed October 10, 2022. https://bit.ly/3Exty36