Targeted treatment of ovarian cancer! US FDA defines the accelerated approval path of mirvetuximab, a new ADC drug, for the treatment of patients with folate receptor positive platinum resistance

December 30, 2019 / BIOON / -- immunogen is a clinical stage biotechnology company focusing on the development of a new generation of antibody drug conjugate (ADC) to improve the prognosis of cancer patients Recently, the company announced that the U.S Food and Drug Administration (FDA) has proposed a new one arm study in platinum resistant ovarian cancer to support the accelerated approval of mirvetuximab soravtansine (imgn853) Based on this guidance, the company will launch the Soraya study, a key trial to evaluate the efficacy and safety of mirvetuximab soravtansine as a single drug therapy in patients who have previously received Avastin (bevacizumab), high expression of folate receptor α (FR α), platinum resistant ovarian cancer "We have had a constructive discussion with the FDA and evaluated all ways to apply mirvetuximab soravtansine faster to patients," said mark enyedy, President and CEO of immunogen We have reached an agreement with the FDA that patients who have previously been treated with bevacizumab but whose disease is progressing with high expression of fr α in platinum resistant ovarian cancer need better treatment We are pleased to launch the Soraya study to assess mirvetuximab soravtansine in this patient population, which, if successful, will enable us to submit accelerated approval applications in the second half of 2021 We expect that the soray study will include the first patient in the next quarter, and we expect to get the top line data in mid-2021 " The company's mirvetuximab soravtansine project now includes two new trials, Soraya and Mirasol: (1) Soraya is a key single arm trial, about 100 patients will be enrolled, and the qualification criteria include the adoption of PS2 + scoring method to confirm the expression of high level fr α, the previous acceptance of up to three schemes and at least one ovarian cancer patient with bevacizumab and platinum resistance The primary end point was the overall response rate (ORR) assessed by the study investigator, and the key secondary end point was the duration of response (DOR) (2) Mirasol is a confirmatory randomized phase III trial in which 430 patients will be randomized to receive single dose chemotherapy (paclitaxel, pegylated liposome doxorubicin, topotecan, once a week) selected by mirvetuximab soravtansine or investigators The eligibility criteria included the use of PS2 + score to confirm the high level of fr α expression, the previous acceptance of up to three regimens and platinum resistant ovarian cancer patients The primary end point was progression free survival (PFS) as assessed by the investigator, and the key secondary end points included overall response rate (ORR), overall survival (OS), and patient reported outcomes Mirvetuximab soravtansine (imgn853) is the first folate receptor α (FR α) targeting ADC Using a humanized fr α binding antibody, ADC specifically targets fr α expressing cancer cells, and uses a powerful anti-tumor agent DM4 to kill the targeted cancer cells In March this year, immunogen released the results of the research on stage III forward-i of mirvetuximab soravtansine in the treatment of fr α positive and platinum resistant ovarian cancer It showed that the study failed to reach the primary end point: in the whole study population, mirvetuximab soravtansine did not significantly prolong PFS compared with chemotherapy However, mirvetuximab soravtansine showed impressive efficacy and tolerability in the pre-defined fr α overexpression subgroup, including PFS prolongation (HR = 0.69, P = 0.049), Orr increase (24% vs 10%, P = 0.014), OS prolongation (HR = 0.62, P = 0.033) In this study, mirvetuximab soravtansine was well tolerated, with fewer patients (46% vs 61%), fewer dose reductions (20% vs 31%) and lower discontinuation rates (5% vs 8%) due to drug-related adverse events The company has reviewed data generated in phase I and forward I studies using PS2 + scoring and identified 70 patients who meet Saraya's key eligibility criteria The data showed that the orr was 31.4% (95% CI: 20.9%, 43.6%) and Dor was 7.8 months (95% CI: 3.98, -) These data are quite good compared with the orr of chemotherapy alone for platinum resistant ovarian cancer In the Aurelia and Corail trials, the orr of chemotherapy alone was only 12%, including the first and treated patients with bevacizumab The repetition of these data in the Soraya study will support the application for accelerated approval before the completion of the Mirasol study After that, the Mirasol study will provide the random data needed to move from accelerated approval to full approval Original source: 1 Immunogen announcements accelerated app roval pathway for mirvetuximab soravtansine in ovarian cancer 2 Immunogen corporate presentation – December 2019