Proactive Investors - GSK PLC (LON:GSK) shares fell despite a double dose of positive news, with the EU medical regulator accepting its application for a myelofibrosis treatment and success in a Phase-3 endometrial cancer trial.
The European Medicines Agency (EMA) validated the marketing authorisation application for momelotinib, the FTSE 100-listed drugmaker’s potential new oral treatment for myelofibrosis, a rare blood cancer.
The drug is not yet approved in any market, but with regulatory reviews from the EMA added to that already started with the US Food and Drug Administration (FDA), approval would make it the only medicine to addresses the anaemia and splenomegaly associated with myelofibrosis, the company said.
Phase-3 trial results earlier this year met all primary and key secondary endpoints.
In a separate statement, GSK said it is planning regulatory submissions for the first half of 2023 for dostarlimab, also branded Jemperli, based on fresh trial results that it said showed a “statistically significant and clinically meaningful improvement” in investigator-assessed progression-free survival of patients with primary advanced or recurrent endometrial cancer.
This cancer is found in the inner lining of the uterus and is the most common gynaecologic cancer in the US and the second most common gynaecologic cancer in the world.
The RUBY Phase-3 trial is the only first-line study to show improvement in progression-free survival for an immuno-oncology therapy in combination with standard-of-care chemotherapy in primary advanced or recurrent endometrial cancer, the company said.
Full results from the trial will be published in a medical journal and presented at an upcoming scientific meeting.
Hesham Abdullah, GSK’s global head of oncology development, said: "Patients with primary advanced or recurrent endometrial cancer have limited treatment options. Long-term outcomes remain poor, and new treatment options are urgently needed to evolve the current standard of care, which is platinum-based chemotherapy.
“Based on these positive headline results from the RUBY phase III trial, GSK intends to seek regulatory approvals for a potential new indication for dostarlimab in the treatment of primary advanced or recurrent endometrial cancer.”
Analysts at Berenberg have forecast revenue from momelotinib of £360mln by 2025 rising to a peak of around £800mln, while for Jemperli they forecast £300mln peak sales.
The shares rose initially on Friday but quickly dropped into the red, down 0.8% to 1,404.4p.