Burning, itching and excruciating pain.
That’s what Kris Kinar felt any time he stepped into sunlight.
The 53-year-old was born with Erythropoietic protoporphyria (EPP), a rare inherited metabolic disorder that causes immediate burning and severe pain when skin is exposed to sunlight.
Kinar grew up in Saskatoon, one of Canada’s sunniest cities, and was forced to spend most of his life indoors, hiding symptoms nobody could explain.
“As your time in the sun increases and that exposure goes up, that tingling turns into an itching sensation, turns into a burning sensation. It becomes excruciating” he told CBC’s The 306.
Kinar said if he were to step out into the sun, warning signs would appear within about two minutes and the reaction could last for days.
He started to feel the effects of the rare, invisible condition as early as three years old, he said.
Throughout his childhood, his parents spent a lot of time visiting family doctors, trying to figure out the cause of his symptoms through blood tests and various medications.
“Even though you very keenly know the symptoms and keenly know what is causing it, you have no idea what was going on,” Kinar said.
He works as a contractor. Up until recently, he had to limit his work to night shifts or jobs that were mainly indoors.
The diagnosis finally came in Kinar’s mid-30s, after he visited a local doctor who by chance was familiar with the disease.
Although a Saskatoon doctor was finally able to identify the cause of his symptoms, Kinar found out there was no cure; avoiding sunlight was his only option.
“It was a bit of a double-edged sword,” he said. “You know you have a name to put to it, but you have the reality that normal will remain normal. That’s what you have to look forward to.”
He kept his condition private because there was always the question in the back of his mind about whether or not people would believe him, “Especially with such a rare thing and especially with something that the reaction has to get so bad that before you can physically see it,” he said.
But Kinar was not willing to give up hope for a better life.
He connected with rare disease organizations in Canada and the U.S., which eventually led him to a clinical trial happening at Massachusetts General Brigham.
That’s where he met Dr. Amy Yeung, attending physician at Massachusetts General Hospital and an assistant professor of medicine at Harvard Medical School. Yeung also lives with EPP; she was diagnosed at age 13.
For the first time, Kinar had found someone who understood both the science and the struggle.
One in 100,000 people is diagnosed with EPP, but “it’s much more common than that,” Yeung said.
“It should be one in about 17,000.”
Yeung said many factors make it difficult to diagnose, including its rarity and the fact that no visible signs are present between reactions. Testing for EPP is different from other conditions in the same class, known as porphyria, she said.
“So some doctors send the wrong test. So many patients can’t find an answer for many years and are diagnosed just by chance, as was Kris’s case.”
Bitopertin, the drug used in Yueng’s medical trial, has been found to decrease the amount of protoporphyrin in the blood by about 50 per cent in patients with EPP, resulting in dramatic improvements to light sensitivity.
“Chris, he’s one example of that,” Yeung said. “Essentially everyone in the study that I’ve seen has had pretty similar results. It’s very exciting.”
Kinar began the medical trial last year. He said he felt relief within the first four days, with a noticeably reduced sensitivity to light.
“It’s almost like a light switch went off,” he said.
He had to track his daily sun exposure every day for two weeks before he started on the Bitopertin. His daily exposure usually averaged eight to 10 minutes, he said.
His world completely opened up on June 14, 2025.
“I went outside on my deck for 127 minutes,” Kinar said.
“It was amazing. I mean, to just have that moment to know that, you know, you’re gonna go watch the kids play ball, you’re gonna go do whatever you want, anything.”
Another big moment came on the Canada Day weekend, only a few weeks into the trial. Kinar was at his best friend’s cabin, where he usually spent most of his time worrying about finding shade.
At one point during the day, his friend urged him to go inside and get out of the sun.
“I said, ‘I don’t have to,’” he said, recalling the teary-eyed moment.
Kinar said he’s now working on rewriting his personal bucket list, this time including all the things “you discard early in your life as not being achievable and realistic.”
He said he has lots of lost time to make up for with his family.
He said he’s sharing his experience with EPP now to raise awareness and offer hope to those who also have a rare invisible illness. If he can help one person, then his story will have made an impact, he said.
Yeung said the findings of Phase 2 of the clinical trial have been published and the trial is now in Phase 3, which is expected to finish this year.
An analysis of the findings will follow, and then hopefully a submission to the FDA for approval, she said.
