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EX - 99.1 2 tm2134074d1_ex99-1.htm EXHIBIT 99.1 Exhibit 99.1 immun - gen ImmunoGen Announces Positive Top - Line Results from Pivotal SORAYA Trial of Mirvetuximab Soravtansine in Ovarian Cancer Trial Met Primary Endpoint with Confirmed Objective Response Rate of 32.4 % Median Duration of Response at Data Cutoff is 5.9 Months Continued Demonstration of Favorable Tolerability Profile BLA Submission on Track for First Quarter of 2022 Conference Call to be Held at 8:00 a.m. ET Today Waltham , MA - November 30 , 2021 – ImmunoGen Inc. ( Nasdaq : IMGN ) , a leader in the expanding field of antibody - drug conjugates ( ADCs ) for the treatment of cancer , today announced positive top - line data from the pivotal SORAYA trial evaluating the safety and efficacy of mirvetuximab soravtansine ( mirvetuximab ) monotherapy in patients with folate receptor alpha ( FR¤ ) -high platinum - resistant ovarian cancer who have been previously treated with AvastinⓇ ( bevacizumab ) . " Despite advances in the platinum - sensitive setting , most patients with ovarian cancer eventually develop platinum - resistant disease , for which there are limited treatment options , especially for those patients who have previously received bevacizumab , " said Robert Coleman , MD , Chief Scientific Officer of US Oncology Research and SORAYA Co - Principal Investigator . " Data from SORAYA have the potential to redefine the standard of care for patients with FRa - high platinum - resistant ovarian cancer , as this trial has demonstrated that mirvetuximab delivers clinically meaningful benefit in this setting , with significant and durable responses and a favorable tolerability profile . " SORAYA is a single - arm study of mirvetuximab in patients with platinum - resistant ovarian cancer whose tumors express high levels of FRx and who have been treated with up to three prior regimens – at least one of which included bevacizumab . The primary endpoint for the study is confirmed objective response rate ( ORR ) as assessed by investigator , including complete and partial responses , and the key secondary endpoint is duration of response ( DOR ) . ORR was also assessed by blinded independent central review ( BICR ) . The study is designed to rule out a 12 % ORR , based on expected outcomes with available single agent chemotherapy from the AURELIA study in patients with platinum - resistant ovarian cancer and one to two prior lines of therapy . Key Findings from SORAYA SORAYA enrolled 106 patients with a median of three prior lines of therapy ( range one to four ) ; 51 % had three prior lines of therapy and 48 % had one to two prior lines of therapy . All patients received prior bevacizumab ; 48 % of patients received a prior PARP inhibitor . As of the data cutoff on November 16 , 2021 , the median follow - up time was 8.1 months . ORR by investigator was 32.4 % ( 95 % confidence interval [ CI ] : 23.6 % , 42.2 % ) , including five complete responses ( CRs ) . ORR by BICR was 31.6 % ( 95 % CI : 22.4 % , 41.9 % ) , including five CRs . Responses were observed regardless of prior PARP inhibitor or number of prior lines of therapy . The median DOR is currently 5.9 months ( 95 % CI : 5.6 , 7.7 ) . With nearly half of responders continuing on therapy , the duration of response continues to evolve and , with longer follow - up , median DOR could range from 5.7 to just above 7 months . Mirvetuximab was well - tolerated , consistent with the known safety profile seen in more than 700 patients treated in the broader mirvetuximab program . Treatment - related adverse events led to dose reductions in 19 % of patients , dose delays in 32 % of patients , and discontinuations in 7 % of patients . The most common treatment - related adverse events included blurred vision ( 41 % all grade ; 6 % grade 3+ ) , keratopathy ( 35 % all grade ; 9 % grade 3+ ) , and nausea ( 29 % all grade ; 0 % grade 3+ ) .