Timing is everything. Having announced on Tuesday that its sickle cell disease drug voxelotor had won US breakthrough designation, Global Blood Therapeutics was able to use its presentation at the JP Morgan meeting yesterday to talk the project up, thereby fuelling a second-day surge in its stock – now up 40% over the past two days.
The designation was awarded partly on the basis of interim data from the first part of voxelotor’s pivotal trial, Hope. Investors seem to have convinced themselves that the full dataset must surely prove the drug’s efficacy – but this will not be revealed for another 18 months. It is pretty early for this level of excitement.
That the breakthrough designation off the back of the interim Hope data was sufficient to drive such a share rise is even more remarkable given that it was just a month ago that another disclosure from that trial caused shares to tumble 14% in a single day. At Ash, GBT announced two deaths from a seven patient compassionate access cohort made up of patients who were otherwise ineligible for the trial (Ash 2017 winners and losers – Déjà vu, December 14, 2017).
The JP Morgan surge put GBT’s shares at their highest historic level, above the frothy heights seen following its initial public offering in the midst of 2015’s biotech bubble. Today investors were happy to take home their winnings, as shares fell 3% in early trading.
Aside from the breakthrough therapy designation, there was little in chief executive Ted Love’s presentation to get especially excited about, but investors getting a contact high is not too surprising. The primary endpoint in Hope is improvement in haemoglobin levels, which phase II data suggest has a good chance of being met in phase III.
The company provided a detailed explanation of a patient-reported outcome tool – a key secondary outcome of the Hope trial – that Dr Love says could provide a more clear-cut result than measuring vaso-occlusive crises because it measures exacerbation of symptoms.
Other phase III projects, notably Pfizer and Glycomimetics’s rivipansel and Novartis’s SEG101 (crizanlizumab), look to prevent vaso-occlusive crises by modifying the inflammatory response in blood vessels, as opposed to GBT’s approach of targeting the underlying cause of red blood cell dysfunction.
|Selected projects in development for sickle cell disease|
|Annual sales ($m)|
|Pedroxa||Ebelle D'Ebelle Pharmaceuticals||Ribonucleotide reductase inhibitor||-||-||-||-||-|
|Voxelotor||Global Blood Therapeutics||Sickle haemoglobin polymerisation inhibitor||-||-||59||232||517|
GBT’s stronger disease-modifying hypothesis may only meet its match in Bluebird Bio’s gene therapy Lentiglobin, still in phase II in sickle cell disease. Should both succeed and get the regulators’ blessings, pricing strategies will be interesting to watch – voxelotor is intended as a once-daily oral medication that patients would need to take for life, while Lentiglobin ought to be a once-and-done treatment that would fix the mutation that causes misshapen red blood cells.
In his JP Morgan presentation, Dr Love claimed treating one sickle cell patient costs “a couple hundred thousand dollars a year”, which if true gives his medical affairs staff an argument for premium pricing for GBT’s small molecule. It would give Bluebird a stronger case for a multi-million-dollar price, although assuming that voxelotor is approved first and becomes the standard of care Lentiglobin’s cost-effectiveness will be measured against voxelotor.
In any case, Dr Love’s lofty target probably needs to be qualified against a 2009 academic review that put the lifetime cost of a single sickle-cell disease patient at $409,000.
In any case, investors have good reason to be excited about voxelotor. The US FDA’s approval of Emmaus Life Sciences’s nutraceutical Endari shows that the bar is low in sickle cell disease. There is reason to hope that even disappointing phase III data for GBT would be sufficient – eventually.
To contact the writers of this story email Jonathan Gardner or Elizabeth Cairns at firstname.lastname@example.org or follow @ByJonGardner or @LizVantage on Twitter. For live updates from the JP Morgan healthcare conference in San Francisco on January 9-12 follow @ByMadeleineA on Twitter.
See our full coverage from the JP Morgan conference here.