Revolutionary melanoma drug Keytruda stuns experts

NZ's skin cancer rates are extremely high. Photo / Thinkstock

A revolutionary skin cancer treatment that shrinks tumours has been made freely available in the UK.

Pembrolizumab, which doctors describe as "jaw-dropping", has approved for use by the UK's drugs rationing watchdog Nice.

According to 3News, the drug has been approved for use in New Zealand, but is not yet funded by Pharmac. Patients need a new cycle of treatment every three weeks and, at a cost of around $10,000 per patient, per cycle, depending on weight, the treatment remains out of reach for many.

It is one of the first of a new wave of "immunotherapy" treatments, which harnesses the body's own immune system and teaches it to attack tumours.

In trials it was shown to be twice as effective as chemotherapy, halting and even shrinking tumour growth for 34 per cent of patients with advanced malignant melanomas. The latest clinical trial results presented at ASCO 2015, showed 80 per cent of advanced melanoma patients who had received no prior treatment, experienced tumour shrinkage and 14 percent had no detectable cancer, at a median follow up of 15 months.

The prospect for patients with advanced forms of skin cancer are grim.

Until five years ago, when drugs started to rapidly improve, patients with advanced melanomas were typically told they should not expect to live for more than six to nine months.

But in one trial, 60 per cent of patients who took pembrolizumab survived for at least 12 months.

The drug is so new that longer-term survival data does not yet exist, but experts say that the 30 per cent to 40 per cent of patients who respond to the treatment should see their lives significantly extended.

Dr James Larkin, consultant oncologist at the Royal Marsden Hospital in London, who led some of the clinical trials of the drug, said today: "I have got patients who have survived for two and a half years, with few side effects.

"It is fantastic that this drug has been approved for use on the NHS. It is unqualified good news.

"It is clear that drugs like this are significantly better than drugs we have had before."

Pembrolizumab, which will be sold under the trade name Keytruda, is the first of a new class of immunotherapies called "anti PD-1 inhibitors" which works by making cancer cells "visible" to the immune system so it can be attacked by the body's natural defence mechanisms.

It is the first treatment to go through the Government's Early Access to Medicines Scheme (EAMS), which enabled 500 people with advanced melanomas to access the drug before it was licensed by the European Medicines Agency earlier this summer.

The new approval means anyone in England with advanced malignant melanoma, for whom another drug, called ipilimumab, hasn't worked, will be able to access the drug on the NHS.

Up to 1,600 patients a year are expected to benefit.

The drug is taken via an intravenous drip every three weeks, with the dose depending on body weight.

For a woman of average weight - about 69kgs - the drug has a list price of £3,682 (NZ$8,800) per dose, totalling £64,000 (NZ$155,000) a year.

Under the terms of the approval, US drug company Merck, Sharp and Dohme (MSD) agreed to give the NHS a discount on the price, the extent of which is commercially sensitive.

Dr David Chao of the Royal Free in London, said last year that early trial results had taken experts by surprise.

"What these early trials are showing is that [these new drugs are fulfilling their promise ridiculously fast," he said.

"Some of these results are really astonishing; almost jaw-dropping."

Gillian Nuttall, founder of Melanoma UK said: "We are delighted that patients with advanced melanoma will now be given another treatment option.

"Melanoma is a very difficult disease to treat and it is good news that this treatment will now be made available on the NHS.

"We must express our thanks to everyone who worked tirelessly in achieving this outcome."

- Daily Mail