Key Points:

Aucklander Steve Koerber considered shifting to Australia to get state funding for the $24,000-a-year medicine that has halted the arthritis deforming his hands.

The 44-year-old real estate agent from Mt Eden began injections of Humira in April for psoriatic arthritis, which was diagnosed when he was 28. The married father-of-three pays for it himself.

"The day after starting Humira I felt like a different person."

He had almost no arthritic pain and had stopped taking painkillers, which had caused great fatigue - "I've got two or three times more energy now."

Mr Koerber had been suffering nausea on a standard, inexpensive arthritis drug which had helped his condition, but not halted it. He expects to keep taking Humira for the rest of his life and says it is unfair Pharmac pays for it for people with rheumatoid arthritis, but not those with his condition.

Pharmac medical director Peter Moodie said the agency was evaluating whether to extend funding of Humira to psoriatic arthritis and another form of inflammatory arthritis, but this would take months and he could give no indication of which way the decision would go.

Psoriatic arthritis affects a tenth of people who have the skin condition psoriasis. It is usually milder than rheumatoid arthritis and is treated with drugs for pain and inflammation.

Mr Koerber has a severe form of the disease, which has eroded his finger joints and left his hands with some of the joints angled sideways. He has had to give up golf and is self-conscious about the look of his hands.

"I got to the situation with my hands that I was having difficulty opening car doors. If I went on holidays it would be my wife who would be carrying the luggage and heavy things."

But while the medicine had halted the disease's progression, the existing damage would remain.

He had considered shifting to Australia where, because he is an Australian citizen, the health system would pay for him to have Humira after he had stayed for six months.

The clinical director of the Wellington Regional Rheumatology Unit at Hutt Hospital, Dr Andrew Harrison, said about 150 people nationwide with psoriatic arthritis or another inflammatory condition, ankylosing spondylitis, would benefit from Humira or a similar drug, called TNF inhibitors. Few could afford to pay for the drugs themselves.

Arthritis NZ chief executive Roger Sowry said New Zealand was well behind Australia and other Western nations in providing comprehensive state-funded access to TNF inhibitors.

He said it was "cruel" that Pharmac had not made a TNF inhibitor available for people with psoriatic arthritis or ankylosing spondylitis.

Abbot Laboratories, which supplies Humira, said it was "working with Pharmac to ensure a listing" of the drug for the two conditions, but the timing was up to Pharmac.

ARTHRITIS MEDICINES

* An estimated 40,000 people in New Zealand have rheumatoid arthritis.

* For most, relatively inexpensive Pharmac-funded drugs control the inflammatory joint disease.

* Pharmac also pays for Humira, a $20,000-a-year drug for patients with severe disease resistant to standard treatments.

* It does not fund Humira for people with the inflammatory conditions called psoriatic arthritis and ankylosing spondylitis.