aibio60 Degrees reports PCR-negative results in five babesiosis patients
Tickers SXTP
All five patients who finished the expanded access study reported improved outcomes and negative conventional PCR tests, and four of five were also negative on a highly sensitive test.
Key facts
- Company
- 60 Degrees Pharmaceuticals, Inc. (NASDAQ: SXTP)
- News type
- Company Updates
- Primary source
- 60 Degrees Pharmaceuticals, Inc. 8-K (2026-10-27)
60 Degrees Pharmaceuticals, Inc. (NASDAQ: SXTP) said on October 27, 2026 that the first five patients to complete treatment with tafenoquine-containing combination regimens in its expanded access study of relapsing babesiosis all reported being much improved or very much improved on study-completion forms. Each of the five had negative conventional polymerase chain reaction (PCR) results for Babesia, documented during treatment or at later follow-up. Four of the five patients, or 80%, were also nonreactive on a highly sensitive blood-donor nucleic acid amplification test (NAT) performed on blood collected after treatment. The press release describes these as clinical and molecular results from the first five completed patients.
Babesiosis is a tick-borne illness. The company says that in immunosuppressed patients, infection can persist or recur despite treatment and can be life-threatening. The expanded access study is open-label and multi-site. It evaluates tafenoquine combined with atovaquone and other antimalarial or antibiotic medications in patients with relapsing babesiosis and risk factors for severe disease. Two additional patients remain on treatment, bringing total enrollment to seven. The study remains open pending potential discussions with the FDA.
What the results show
One of the five patients had a reactive blood-donor NAT result despite a negative follow-up conventional PCR result from the Mayo Clinic. The NAT samples from the five completed patients were collected 66 to 120 days after tafenoquine treatment ended. The company describes the NAT assay as 500-fold more sensitive than conventional PCR and says it is not routinely available for patient care. The evidence is thin: five patients, no control group, improvement reported on study-completion forms rather than by a blinded assessment, and one of five still reactive on the more sensitive test.
The release also compares the company's approach with published cases. The company reviewed published relapsing babesiosis cases and found that six of seven patients (85.7%) treated with tafenoquine-atovaquone combinations remained retreatment-free for at least 12 weeks. It says that is approximately 3.6 times the model-estimated 23.5% expected from conventional treatment, after accounting for the duration of atovaquone, the other medications and prior treatment history. In an exploratory Cox comparison, the company reports a two-sided p = 0.019 from an approximate, patient-clustered score test. The comparison is against published case reports, not a randomized trial, and the 85.7% rests on six of seven patients.
The regulatory path
The company plans to pursue accelerated approval if the efficacy section of its registration dossier is based primarily on data from immunosuppressed patients with relapsing babesiosis. The FDA has not agreed to this path. In that case the company would propose post-treatment blood-donor NAT nonreactivity as a surrogate endpoint reasonably likely to predict durable clinical benefit, with a postmarketing confirmatory study.
Tafenoquine is not FDA-approved for babesiosis. It is approved in the United States for malaria prophylaxis under the brand name ARAKODA, with approval in 2018 and commercial availability in 2019.
Financial position
According to the annual report filed March 30, 2026, revenue was $1.0 million in 2025, compared with $607,574 in 2024. Research and development expense was $2.1 million in 2025 and $5.0 million in 2024. The net loss was $7.4 million in 2025 and $7.9 million in 2024. Cash from operations was negative $6.8 million in 2025 and negative $5.6 million in 2024. Cash and cash equivalents were $1.7 million at year-end 2024. The quarterly report filed August 14, 2026 gives cash and cash equivalents of $1.5 million and short-term investments of $1.2 million at December 31, 2025, and cash and cash equivalents of $1.0 million at June 30, 2026, against $6.8 million of cash used in operations in 2025.
What comes next
The company expects to unblind its separate randomized, placebo-controlled study of tafenoquine or placebo, added to standard-of-care therapy in patients hospitalized for babesiosis, in January 2027. After unblinding, it intends to request a pre-supplemental New Drug Application meeting with FDA to discuss data from the hospital and expanded access studies and the appropriate regulatory pathway for tafenoquine in babesiosis. Until then the expanded access study stays open, and two more patients remain on treatment.