AbbVie builds the case for ovarian cancer drug Elahere

AbbVie's Elahere has been shown to reduce the risk of death in patients with folate receptor-alpha (FRα) positive, platinum-resistant ovarian cancer by a third, reinforcing its blockbuster credentials.

New data from the phase 3 MIRASOL trial presented at the Society of Gynaecologic Oncology (SGO) Annual Meeting on Women's Cancer in Seattle over the weekend showed that, after more than 30 months of follow-up, overall survival was 32% improved with Elahere (mirvetuximab soravtansine) compared to chemotherapy.

Median OS came in at nearly 17 months for the Elahere group, compared to just over 13 months for chemo, while median progression-free survival (PFS) was 5.6 and 4 months, respectively.

The study enrolled adults with platinum-resistant, FRα-expressing high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who have received one to three prior systemic treatment regimens. FRα is considered a marker of tumour aggressiveness, associated with poorer response rates to treatment, and is over-expressed in around a third of ovarian cancer patients.

The new survival data comes as AbbVie is already seeing strong take-up of Elahere, which was the centrepiece of its $10.1 billion takeover of ImmunoGen in 2023. The drug was given accelerated approval in the US in 2022, which was upgraded to full approval a year ago, and was also cleared in Europe last November.

AbbVie has pointed to a very strong launch trajectory for Elahere, with sales rocketing to $480 million last year, almost entirely from the US market and before the contribution from Europe was ready to kick in. It is modelling sales of $750 million this year.

The drug has the potential to revolutionise the management of patients with this type of cancer, according to AbbVie, which notes the lack of treatment options for women whose disease stops responding to platinum-based chemotherapy. Elahere is the first drug to improve survival in platinum-resistant ovarian cancer.

"Ovarian cancer can be devastating and, when cancer cells stop responding to chemotherapy, patients may feel hopeless about their journey," said Svetlana Kobina, AbbVie's head of oncology medical affairs.

"The data presented today reinforce[s] the importance of Elahere as a transformative therapy for patients with limited options," she added.

AbbVie is also trying to extend the indications for the FRα-targeting antibody-drug conjugate (ADC), with a phase 3 study on the go in platinum-sensitive ovarian cancer, and will also be tested as a combination therapy with bevacizumab, carboplatin, and a PARP inhibitor. The company also has a follow-up FRα-targeting ADC – IMGN-151 – which is in phase 1.

GlobalData has predicted that, with its first-to-market advantage, Elahere could generate $2.8 billion in 2029. One potential rival is Eisai's farletuzumab ecteribulin, another ADC that was licensed to Bristol Myers Squibb (BMS) in a $3.1 billion deal that was dissolved last year. Eisai is testing the drug in a pair of phase 2 trials in ovarian and non-small cell lung cancer (NSCLC).