Among the plethora of data being presented on melanoma treatments at the American Society of Clinical Oncology meeting in Chicago, Amgen has presented promising detailed late-stage data on talimogene laherparepvec, also known as T-Vec.

T-Vec is an oncolytic immunotherapy which is injected directly into tumour tissue and then replicates until the membrane of the cancer cells rupture, thereby destroying them. The virus contained in these cells is then released locally in the tumour tissue along with granulocyte-macrophage colony-stimulating factor (GM-CSF), a white blood cell growth factor that the virus is engineered to express, which kill tumour cells throughout the body.

Updated Phase III data was presented at ASCO evaluating T-Vec in patients with unresected stage IIIB, IIIC or IV melanoma compared to GM-CSF. The study met its primary endpoint of durable response rate (DRR), defined as the rate of complete or partial response lasting continuously for at least six months.

A statistically significant difference was observed in DRR with 16% in the T-Vec arm versus 2% in the GM-CSF arm. The overall response rate was 26% vs 6% and Amgen noted that a trend toward overall survival was also observed in an interim analysis.

Amgen R&D chief Sean Harper said "these are the first data from a controlled trial of oncolytic immunotherapy to demonstrate activity in melanoma". He added that "we look forward to the mature overall survival data later this year".

Howard Kaufman of the Rush University Medical Center in Chicago, who presented the data, told PharmaTimes World News that this "totally new approach" could represent a paradigm shift in the treatment of melanoma. He was particularly pleased about the side effect profile, noting that patients are injected and may feel flu-like symptoms for a few minutes but "can take a Tylenol and carry on with their daily lives as normal".

He also spoke about the potential of using T-Vec in combination with drugs particularly with investigational PD-1 antibodies, such as Merck & Co's  lambrolizumab and Bristol-Myers Squibb's nivolumab. More on the PD-1 drugs later in the week.