Shares in the Danish biotech Genmab soared 13% to a record high today in the wake of phase II data on its hotly-tipped multiple myeloma treatment, daratumumab. With breakthrough therapy designation in hand in this particular setting and the FDA showing itself very willing to act swiftly on these projects, investors are betting that the odds of a 2015 approval just got shorter.
Last year the US regulator approved nine projects with this classification, with an average of four months between receipt of an application and a green light, according to a recent EP Vantage analysis. Assuming the full data are equally impressive partner Johnson & Johnson will no doubt be harbouring similar regulatory ambitions for what is one of its most promising pipeline projects (Breakthrough designation quickens FDA approval pace in 2014, January 5, 2015).
The anti-CD38 antibody is the most advanced of its class and analysts tracking the pharma giant reckon it could be selling $627m by 2020, consensus data from EvaluatePharma show. Peak sales estimates stretch into the billions, however, and this mechanism generated much excitement at last year’s ASH meeting.
Data were released today from a study called Sirius or MMY2002, a two-part test that enrolled 124 double-refractory patients. They had received at least three prior lines of therapy and were unresponsive to the two mainstay mechanisms of action in this disease – proteasome inhibition with drugs like Velcade or immunomodulation with drugs like Revlimid.
Revlimid, Velcade and Pomalyst have made a huge difference to multiple myeloma over the last decade. However there remains a major need in this so-called salvage setting, where patients on average live for barely nine months. Daratumumab was one of the first agents to receive the FDA’s breakthrough therapy designation back in May 2013 in this setting.
The study generated an overall response rate of 29.2% in the 16 mg/kg group – the regimen being used across J&J’s extensive phase III programme - and a median duration of response of 7.4 months.
Analysts at Jefferies who track Genmab commented that the results exceeded their “base case expectations”, noting that a meaningful number of patients were likely to have received the more recently-approved myeloma drugs Kyprolis and Pomalyst.
Expecting no less
Both of these drugs are forecast to become major products in this space in the coming years, despite only being approved currently in refractory settings based on response rates. Expectations are that they will prove themselves in earlier lines of therapy and go on to fight for market share with existing proteasome inhibitors and immunomodulators.
The advantage of daratumumab is of course its novel mechanism of action: it targets the CD38 antigen, which is expressed in around 98% of multiple myeloma patients. Data presented at ASH last year pointed to the additional potency that such an agent can contribute to currently used regimens, prompting predictions that the anti-CD38 antibodies would also move to front line use (ASH – Multiple myeloma therapy goes combo, December 6, 2014).
More evidence is needed to confirm this potential, of course, and phase III data are some way away. J&J has three pivotal studies underway - two in a refractory setting and one in untreated patients with a second, first-line study due to start soon – but results are unlikely to emerge until late 2016 at the earliest.
However the full Sirius data could be unveiled at this year’s ASCO cancer conference, and a US regulatory filing this year is not beyond the realms of possibility.
Genmab shares were trading at DKr47.90 this afternoon, giving the company a market value of DKr26.7bn ($4.1bn). Considering that the stock has almost doubled in the last three months alone, it seems that investors are expecting nothing less.