Tick Pills

There is a great old TV cartoon called "The Tick." It’s deliciously smart and heady. (It featured a superhero called the Crusading Chameleon, whose weakness was traversing over complex colors. "Can’t do plaid," he would say before passing out.) Its titular character was very powerful; like his namesake, he was "nigh-invulnerable."

Ticks are VERY hardy and very problematic. They are the prime carrier of Lyme disease, which is no walk in the park (pun intended).

Now, if you own a dog, you know there’s a tablet (often encased in aftermarket peanut butter) to prevent ticks. If it’s good enough for dogs, why don’t we humans have an equivalent?

I’m glad I asked because Tarsus Pharmaceuticals is developing such a pill to provide people protection for at least several weeks at a time. It’s early, but it’s looking good, as the company has announced results from a small, early-stage trial showing that 24 hours after taking the drug, it can kill ticks on people, with the effects lasting for up to 30 days.

Lyme disease sucks and is getting to be a real problem. It is estimated that more than 475,000 people are diagnosed and treated for it each year. That’s not even the worst number associated with the mysterious disease; researchers at the CDC and Yale University put the cost to our healthcare system at almost 1 BILLION dollars.

The disease (bacteria Borrelia burgdorferi) is passed to humans through the bite of an infected tick. Symptoms include fever, headache, fatigue, and a characteristic skin rash that looks like a bullseye. Lyme disease can sometimes cause serious health issues. If left untreated, the infection can spread to the joints and cause arthritis. It can also become established in the heart and nervous system, causing persistent fatigue, numbness, or weakness.

Stock Photo of Infected female deer tick

So we need a better strategy than DEET or covering ourselves in hot clothes. Enter Tarsus’s pill. The experimental medicine is derived from lotilaner, a drug that paralyzes and kills parasites by interfering with the way that signals are passed between their nerve cells.

In recently concluded Phase II trial, 31 healthy adults took either a low or high dose of the Tarsus pill, or a placebo. Researchers then placed sterile ticks on participants’ arms and, 24 hours later, measured how many died. They also observed tick death 30 days after a single dose of the pill. At day one, 97 percent of ticks in the high-dose group and 92 percent in the low-dose group had died, while only 5 percent of ticks in the placebo group had. One month out, both doses of the pill killed around 90 percent of ticks.

“The takeaway is that it killed the ticks really quickly, and the effect lasted for a long time.”

There are other tick-borne diseases so a drug that targets ticks in general will have broader benefits. Further, due to changes in climate and rapidly growing deer population and the housing extension into deer habitats, we are seeing evidence that ticks are expanding their ranges.

What should stopping ticks via a pill just be the providence of dogs? That’s a good question and soon we will have a good answer, it seems.