The therapeutic cancer vaccine field has had numerous setbacks, but a path to salvation might be opening up to players in this space in the form of combinations with immuno-oncology drugs. Transgene is the latest to try this approach, with a deal that will see it test its therapeutic HPV vaccine TG4001 alongside Pfizer/Merck KGaA’s anti-PD-L1 monoclonal antibody avelumab in head and neck cancer.
However, the company faces stiff competition as others flock to combine their compounds with PD-1/PD-L1 inhibitors, which led some analysts to greet the latest news with cautious optimism. “Competition is intense – but this is true in oncology in general,” Trangene’s chief executive, Philippe Archinard, told EP Vantage.
AstraZeneca, for one, has already set out its stall as the immuno-oncology combination specialist to beat (Asco – Check mate for combination promise and shortcomings, May 31, 2015). The company is trialling its PD-L1 antibody durvalumab with a range of different molecules including Inovio’s HPV vaccine INO-3112 – putting it in direct competition with Transgene.
Transgene did not give financial details of its collaboration, under which it will evaluate the combination in HPV-positive head and neck cancer after failure of standard therapy, with a phase I/II trial slated to start in the first half of 2017.
Oddo Securities analysts noted that the financial terms “are likely very low” and that “the two pharma groups will probably offer avelumab to Transgene for its trial for free”. Mr Archinard did not confirm this but said that the merit of the agreement goes beyond financial elements, and that working with Pfizer and Merck KGaA would help open doors for Transgene.
The phase I/II results, if positive, could leave the door open to update the collaboration “with up-front, milestone and royalty payments”, the Oddo Securities analysts added.
Mr Archinard would not say when data from the phase I/II study will become available – however, analysts have predicted sometime in 2018. But Mr Archinard commented that it “will not take hundreds of patients” to reach a target response rate of around 15%.
This might seem low, but he cited a huge unmet need for patients, adding that median progression free survival in HPV-positive head and neck cancer is currently around three months.
HPV-positive cases account for around 60% of head and neck cancer patients, Mr Archinard said, adding that the number is rising. This is thought to be down to increases in numbers of sexual partners and oral sexual behaviour.
Transgene is therefore targeting a growing niche. In addition, responses in HPV-positive head and neck cancer to PD-1 monotherapy have been less impressive than in other indications.
But the company is also looking beyond niche indications, with its lead compound, the MUC1 vaccine TG4010, being trialled in combination with Bristol-Myers Squibb’s Opdivo in second-line non-small cell lung cancer, and alongside an unnamed checkpoint inhibitor in first-line NSCLC. More details on the second combination should emerge next year.
A while ago, cancer vaccines had looked dead and buried. Now, the combination approach is helping to give it some signs of life.
EP Vantage has published a broad overview of the current landscape for anti-PD-1/PD-L1 combination therapeutics. A free copy of the report is available by download.