Melanoma NZ chief executive Linda Flay said she believed the cost was worth it even if not everyone could be guaranteed results.
"If 30, 40, 50 per cent are getting a response, it's better than sending people away with no help," Flay said.
"Before this there was a huge unmet need for [treating] advanced melanoma. This allows them to have hope to increase their life expectancy that they didn't have before."
She was heartened by the decisions to fund Opdivo and Keytruda but said there was still a need for people who were too sick for immunotherapy drugs.
She said gene therapy drugs such as Debrafenib also needed to be funded by Pharmac to give the worst sufferers a chance.
Cancer patient Leisa Renwick last year successfully campaigned for funding for Keytruda so that everyone with late-stage melanoma could access the drug, which costs $8500 every three weeks.
Her petition gained more than 11,000 signatures and was referred to the Health Select Committee but in May the Government acted before submissions were heard and gave Pharmac another $39m to fund Keytruda and Opdivo.
She told the Herald she was pleased by how many people had benefited from the drug.
"I think it's great. It's really good news. It's just unfortunate how hard it was to get the funding in the first place and we're still not where other countries are."
A good example of that was Dabrafenib, one of the drugs which saved her life, she said.
When Renwick was diagnosed in 2015 she was too sick for Keytruda. She was first prescribed Dabrafenib which helped improve her health to the point where immunotherapy could work.
"The only reason I'm alive now is that the oncologist had the ability to give me exactly what I needed at the right time. It's fantastic that people are getting treatment here but without that ability it's no good."
Because the drugs responded differently in different people, a wider range needed to be available, she said.
Pharmac director of operations Sarah Fitt said Dabrafenib had been reviewed by clinical advisers who recommended its funding application be declined because of the associated toxicity, uncertainty about the benefit and duration of benefit, the cost and recent funding of other drugs like Opdivo and Keytruda.
Breast Cancer Foundation NZ research manager Adele Gautier said the organisation was excited patients now had access to Perjeta.
Perjeta is used in conjunction with Herceptin, another breast cancer drug, and significantly improved the effectiveness for many people.
"Advanced breast cancer is currently incurable. These drugs are sometimes giving years more life to people," she said.
"It really is a great medicine for advanced HER2+ cancer. The clinical trials have shown great results for people with Perjeta. It really is the standard of care internationally."
The foundation was now fighting to get funding for the 160 women who were already using Herceptin to be given Perjeta as well, she said.
Pharmac confirmed its clinical advisers had been asked to give their view on the issue so a decision on whether to extend the funding could be made.
While funding Perjeta was a great victory, all the drugs available for late-stage breast cancer eventually stopped working so more drugs were needed to continue to prolong lives, Gautier said.
Health Minister Jonathan Coleman said Pharmac's model for increasing subsidised treatments was world class.
"The funding boost in Budget 2016, an extra $124 million over four years, means that Pharmac can further increase access to new medicines, benefiting more New Zealanders."
New immunotherapy treatments approved by Pharmac
Opdivo (Nivolumab)
Initial applications approved: 61
Renewals approved: 32
Keytruda (Pembrolizumab)
Initial applications approved: 223
Renewals approved: 72
Perjeta (Pertuzumab)
Initial applications approved: 34
* Applications approved up until the end of January, 2017
