U.K. biotech PsiOxus Therapeutics has a green light for trials of its cancer-killing virus therapy for solid tumors, sparking a $15 million milestone payment from development partner Bristol-Myers Squibb.
BMS bought into the program a year ago with a $50 million upfront payment to secure rights to NG-348, an "armed" oncolytic virus, plus a pledge for milestones that could add another $900 million-plus to the tally if development goes according to plan.
Unlike regular oncolytic viruses, PsiOxus has developed a way to use them as a vehicle to deliver genes, potentially expanding the potency and flexibility of the approach.
The latest biobucks installment for the Oxford-based company—one of this year’s Fierce15 picks—has been activated by regulatory approval to start human clinical trials of NG-348—the first time that one of PsiOxus’ systemically delivered, intravenous anticancer gene therapy candidates has reached that stage of development, said John Beadle, M.D., the firm’s CEO, in a statement.
NG-348 virus uses PsiOxus’ tumor-specific immuno-gene therapy (T-SIGn) platform to arm the virus with two additional immuno-therapeutic transgenes. The idea is that the virus replicates within cancer cells and not within normal tissue, causing an inflammatory response that encourages lymphocytes to collect and attack the tumor.
Arming the virus with could add another level of activity, and in the case of NG-348 the additional sequences code for human CD80 and an antibody fragment specific for the T-cell receptor CD3 protein, both of which are designed to encourage a stronger immune response. PsiOxus has also discussed incorporating sequences coding therapeutic antibodies such as anti-PD-L1 and anti-CTLA4.
The clinical trial of the viral therapy will be conducted by BMS, according to PsiOxus. The two companies have also been collaborating on an ‘unarmed’ variant of the oncolytic virus—called enadenotucirev—since July 2016. That project has already passed phase 2 trials and in a phase 1/2 study in ovarian cancer. The virus can be administered intravenously, unlike oncolytic virus pioneer Imlygic (talimogene laherparepvec) from Amgen which needs to be administered directly into tumors.
There had been speculation that privately-held PsiOxus may be tempted to file an initial public offering this year, but as yet there is no news on those plans and the company has suggested it has a number of other partnerships in its sights that could postpone an IPO until 2019.