How a promising new drug may help combat baldness caused by alopecia

A cure for patchy baldness may be on the way, according to a new study published Sunday in the journal Nature Medicine.

Unfortunately, the treatment is expensive. It currently costs between $7,000 and $9,000 a month. And, it only treats hair loss caused by an autoimmune condition called alopecia areata.

But for the men and women who suffer from alopecia (2% of the overall population), this could be big news.

“It is not a life-threatening form of autoimmunity, however it is a life-altering form of auto-immune disease,” said Angela Christiano, a genetics specialist at Columbia University in a video describing the new research. “It affects patients in a very profound, very personal way to undergo hair loss.”

People who have alopecia lose their hair in patches mostly on their scalp, but occasionally they can also lose hair from other parts of their body. Christiano suffers from alopecia herself and has been studying the disease for 15 years.

Scientists have known for decades that alopecia occurs when the base of the hair follicle gets attacked by a swarm of the body’s own T-cells, which causes the hair to fall out and the hair follicle to go dormant. But it was only recently that they determined what was causing the swarming to take place in the first place. Four years ago, Christiano published a study that found the hair follicles themselves release a signal that attracts the T-cells to them.

Christiano wondered if it would be possible to block the signal that the follicles were putting out, so that the T-cells would not swarm. She began working with Raphael Clynes, a physician and immunologist also at Columbia University. They found that a new type of drug called a JAK inhibitor could interfere with the messages the two types of cells were sending to each other.

“We think the JAK inhibitor acts on both the T-cell and the hair follicle,” said Clynes, in an interview with the Los Angeles Times. “The two are in a dance -- the T-cells get activated, and the hair follicle starts upregulating all the things that make it attractive to the T-cell. The JAK breaks both pieces of the cycle.”

The researchers tested their theory on mice with the disease, using two different JAK inhibitors approved by the Food and Drug Administration. When the mice grew back all the hair they had lost, the team decided to test one of the JAK inhibitors on a very small group of people.

They chose to use just one of the JAK inhibitors called ruxolitinib. It is the more expensive of the two, but it has fewer side effects. Ruxolitinib has been approved to treat a bone marrow disease. Studies show that it may compromise a person’s immune system if it is used for a long time, but Clynes said alopecia patients would probably need to take the drug for no more than six months for it to be effective.

The trial started with just three participants with moderate to severe alopecia, and for each of them, their hair growth was restored within four to five months. The researchers have since expanded the trial to 12 participants.

“We are ecstatic with the early response rate,” said Clynes.

Still, don’t expect ruxolitinib to be approved by the FDA for treating alopecia within the next couple of years. The team needs to run a much larger trial, and to make sure that the drug is safe for people to take for an extended period of time.

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