Coiled Therapeutics (AIM:COIL), the clinical-stage oncology company, has reported a significant improvement in efficacy from its experimental cancer drug AO-252, with a twice-daily dosing regimen delivering an 80% clinical benefit rate in its latest trial cohort, sending its shares up 13% to 9.66p.
The result compares favourably with the 40% clinical benefit rate recorded in the preceding once-daily cohort, and comes as the company prepares to move into targeted dose expansion in ovarian and prostate cancer.
AO-252 is a first-in-class inhibitor of TACC3, a protein involved in cancer cell division, and is being evaluated in a phase I/II trial in patients with advanced solid tumours.
Thirty-one patients have been enrolled to date, with 21 evaluable for efficacy.
In the twice-daily cohort, four out of five evaluable patients achieved tumour stabilisation or regression, with treatment durations exceeding six months.
That substantially outperforms the two to three months typically seen with salvage therapy in heavily pre-treated patients, defined in this trial as those who had received a median of five prior lines of treatment.
A leiomyosarcoma patient, a form of soft tissue cancer, achieved stable disease after just two cycles of AO-252 despite having received nine prior therapies.
No serious adverse events have been observed and the maximum tolerated dose has not yet been reached, allowing dose escalation to continue.
The company said emerging data also points to a dual mechanism of action, with AO-252 appearing to activate the immune system via the cGAS/STING pathway in addition to its direct anti-tumour effects.
This pathway plays a role in triggering the body's immune response to cancer cells, and its activation could make AO-252 a candidate for use alongside immunotherapy agents.
Coiled said it is actively developing a combination therapy protocol, with study initiation targeted for the third quarter of 2026.
Pharmacokinetic analysis has identified differences in drug exposure between male and female patients, which the company said it is incorporating into dose modelling as the programme advances.
A next-generation formulation of AO-252, designed to improve drug absorption and duration of effect, is on track for introduction in mid-2026.
Dose escalation is expected to complete in the first half of 2026, with the company targeting enrolment of 40 patients in focused ovarian and prostate cancer cohorts by the third quarter.
Chief executive Sridhar Vempati said the BID data was "transformative" and described 2026 as a potentially transformational year for the company, with multiple data readouts expected across the year.
Comprehensive expansion cohort data in ovarian and prostate cancer are anticipated in the second half of 2026, alongside potential planning for a phase II registrational trial.