Myovant says its first phase 3 trial of uterine fibroids drug relugolix met its objectives in the first of two phase 3 trials, but its shares dropped on concerns about how well it can compete with an AbbVie rival.
The company, part of the Swiss Roivant group headed by Vivek Ramaswamy, reported that 73% of women with uterine fibroids and heavy menstrual bleeding who were treated with relugolix responded to treatment, meeting a threshold for a reduction in blood loss, compared to 19% of the placebo group. Both the drug and placebo were given on top of oestradiol and norethindrone.
Myovant’s drug – a GnRH antagonist – also hit the mark on a number of secondary endpoints in the LIBERTY 1 trial, including pain, quality of life, and anaemia, and the company also said the once-daily oral treatment appeared to be safe and well-tolerated.
Uterine fibroids are non-cancerous tumours that form in the muscle walls of the uterus and affect between 20% and 80% of women by the age of 50. In many cases they cause no symptoms, but around a quarter of women experience pain, abnormal bleeding and other symptoms, and may experience fertility problems.
The biotech said it was “incredibly pleased” with the results, so the steep drop-off in its shares – down 25% – suggests that investors are not convinced that the drug will be able to take on AbbVie and Neurocrine Biosciences’ GnRH antagonist elagolix. Their drug is already approved as Orilissa to treat endometriosis and has two positive phase 3 readouts in uterine fibroids in hand.
Top-line results from those trials put the response rate for elagolix in the same ballpark as relugolix, and as AbbVie’s drug is given twice-daily rather than once-daily the pressure on Myovant seems to stem from concerns that the company will be able to compete commercially with its larger, deep-pocketed rival.
AbbVie is also set to reach the market first, with a filing in uterine fibroids due in the latter half of this year while Myovant’s second phase 3 trial is still to report and relugolix filing will likely be several months behind elagolix. In Myovant’s favour is that relugolix is also already on the market in Japan, where it is sold by Takeda.
Analysts at Baird suggested that one reason for the fall might be financing concerns as Myovant approaches what could be an expensive registration and roll-out process, although they said the drug has “blockbuster potential in uterine fibroids and endometriosis.”
Meanwhile, also in hot pursuit is Swiss biotech ObsEva with linzagolix (OBE2109), another GnRH antagonist that is currently in a pair of phase 3 trials in uterine fibroids.