A scheme that offers free drugs for people facing large medical bills is being seen as papering over the cracks in our drug-funding system.

A Nelson man with non-Hodgkin lymphoma, who was facing a bill of $500,000, has managed to get free treatment through the drug maker's Compassionate Access Programme.

Cancer Society medical director Chris Jackson told Mike Hosking if a drug is good, it should go through Pharmac in a timely way.

"It doesn't and that's why we have these schemes - because our current drug funding system isn't really up to scratch

"It's too slow, too cumbersome and we have poorer access than our comparative countries."

Oncologists have described the scheme as a marketing tool drug companies use to promote products that aren't approved by Medsafe.

They warn supply of medication could stop, if Medsafe approves the drug and the patient is then stuck not being able to afford ongoing treatment.

Chris Jackson says the gap between New Zealand and the UK has never been bigger than it is now when it comes to access to drugs.

"The UK has managed to get ways of getting these new drugs to patients quicker than we have and Pharmac's operating under a model that is 25 years old. Frankly the world has changed."

Chris Jackson says we need a national cancer agency because treatment varies, depending on where people live.