Tarsus Pharmaceuticals said Monday its lotilaner eyedrop cured the eye condition collarette at Day 43 for patients with Demodex blepharitis, or eyelid mange, in a pivotal phase 2b/3 trial that sets the biopharma up for an FDA filing next year.
Eight months after going public, the results are a “landmark” for Tarsus on its path toward selling the drug, TP-03, for a disease “hiding in plain sight” without an approved treatment, said Tarsus CEO and President Bobak Azamian, M.D., Ph.D., in an interview.
The Saturn-1 study showed that 81% of patients had significant clinically meaningful collarette cure at Day 43. The study of TP-03 also met all secondary endpoints, including eradicating mites in 68% of patients at Day 43 in the trial, which enrolled 421 patients over the age of 18, the company said. The eyedrop was administered twice a day in each eye for six weeks.
TP-03 uses lotilaner, which Azamian described as the “latest and best drug to treat mange in animals” as well as to prevent other parasitic infestations such as fleas and ticks.
There were no treatment-related discontinuations, and more than 90% of patients reported the drop to be neutral to very comfortable, with more than half, at 55%, describing the treatment as very comfortable, Azamian said. Close to 12% of patients in the active group cited instillation site pain/burning/stinging.
Tarsus expects to file for regulatory approval next year for the treatment following readouts in the first quarter of 2022 for a second pivotal trial, Saturn-2, which is an identically sized and designed trial, Azamian said. Tarsus chose to begin that trial in May before releasing today’s results, because the company was “confident that we would have great results based on prior studies that we’d done.”
A regulatory approval could impact nearly 1 in 12 Americans, as 25 million people in the U.S. have the disease, Azamian said.
Azamian described the eyedrop as feeling similar to a “rewetting drop, as many of us use” and is a long-acting drug that is “lipophilic, or oil loving, so it’s perfectly suited to get into the oily tissues of the eyelids, the sweat glands where the mites actually reside and infest and cause inflammation and disease.”
Blepharitis is a disease that has been understood for a long time but has lacked a treatment, Azamian said. Tarsus pursued Demodex because it’s a major cause of blepharitis that occurs in 58% of patients that enter an eye care doctor’s clinic, based on the company’s research, the CEO said.
“It’s also a contributor and a complicator of other important eye diseases—dry eye, cataract surgery and the outcomes resulting from that and contact lens intolerance. So it’s a disease that, as we say, is hiding in plain sight that doctors can easily diagnose if they just have patients look down in the eye exam chair and look for this specific collarette,” Azamian said.
Tarsus has global ambitions for the drug and inked its first partnership with LianBio in China in March.
That deal, which gave Tarsus $15 million upfront and up to $185 million in milestones, provides Tarsus with access to “an equally sized market as the US with a really innovative and aggressive partner in all the right ways,” Azamian said. TP-03 is “roughly a year behind in China where it is today in the U.S.,” he added.
“We’re excited to partner with Lian Bio because they’ve done this in other spaces like cardiovascular medicine and oncology and now looking at inflammation. We are the anchor asset to their ophthalmology ambition,” Azamian said.
Tarsus has not determined yet whether it will advance the drug itself in other markets such as Europe and other regions in Asia, but the company will “certainly be looking” at partnerships for TP-03 and its two other assets: TP-04, a skin cream for rosacea, and TP-05, a pill for Lyme disease.
Last week, Tarsus said it initiated the phase 1 trial for TP-05, a novel, oral treatment meant to kill ticks before transmitting Lyme disease. The company also expects to be in phase 2 trials for TP-03 within 12 months for another eye indication, Meibomian gland disease, which is a mite infestation at the back of the eyes contributing to dry eye, Azamian said.
Tarsus has a dry eye expert on its leadership team in Chief Commercial Officer Aziz Mottiwala, Azamian said. Mottiwala was vice president of marketing for the eye care unit of Allergan, now part of AbbVie, which included dry eye treatment Restasis, which pulled in $1.14 billion in sales in 2019.
The eye care market also got a boost last week when LENZ Therapeutics, formerly Presbyopia Therapies, pulled in $47 million for clearer line of sight for its farsightedness eyedrop treatment.