Key Highlights

  • Cleo Diagnostics (ASX:COV) shares were up 4.92% at $0.32 during the trading session on 23 October 2026, as at 12:04 pm.
  • In an announcement dated 21 October 2026, the company reported its prototype screening test met its targets in a 247-person proof-of-concept study.
  • Development now moves to bridging and expanded cohort studies, while the pre-surgical triage test progresses toward an FDA submission early next year.

Cleo Diagnostics Ltd (ASX:COV) shares were up 4.92% at $0.32 during the trading session on 23 October 2026, as at 12:04 pm, while the S&P/ASX 200 stood at 8,762.60, down 0.35% (30.60 points) at the same time. Cleo is an Australian medical technology company developing a blood test for the early detection of ovarian cancer, and in an ASX announcement dated 21 October 2026 it reported results from the first proof-of-concept study of its prototype screening test.

Proof-of-Concept Study Results Reported

In its announcement dated 21 October 2026, Cleo stated that its prototype ovarian cancer screening test met or exceeded all pre-defined performance targets in its first proof-of-concept study. The retrospective study involved 247 women, comprising 87 healthy individuals, 67 women with benign gynaecological disease and 93 women with ovarian cancer, including 62 cases of Stage I disease.

For high-risk population screening, the minimum targets were 90% sensitivity and 90% specificity. In Stage I cancer detection the prototype recorded 92.2% sensitivity and 98.7% specificity, and in all-stage detection 90.2% and 97.4%. For general population screening, the targets were 75% sensitivity and 99.6% specificity, and the prototype recorded 75.0% and 100.0% for Stage I.

Comparison With CA125 and Study Limitations

The announcement dated 21 October 2026 also compared the prototype with CA125, which the company described as the current clinical gold-standard biomarker. The prototype's area under the curve (AUC) was 0.99 for Stage I cancers, against 0.83 for CA125, and 0.98 for all-stage cancers, against 0.87 for CA125.

Cleo noted that the results are estimates from a retrospective proof-of-concept cohort and require confirmation in larger, independent and intended-use populations. The company also stated that there is currently no clinically adopted screening test for ovarian cancer.

Staged Screening Program and Next Steps

According to the 21 October 2026 announcement, the first stage of the screening development program is complete. The next stage is bridging and expanded cohort studies in a larger independent cohort, intended to confirm the initial estimates, improve statistical power and assess reproducibility.

The third stage is evaluation using prospectively collected samples, which the company said have already been collected and include samples from the UK Collaborative Trial of Ovarian Cancer Screening and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Cleo also intends to submit the results for publication in peer-reviewed literature, and said development will proceed in parallel with its pre-surgical triage test, which is progressing toward an FDA submission early next year.

About the Company and Business Overview

Cleo Diagnostics Ltd is listed on the ASX under the code COV and is headquartered at Level 2, 480 Collins Street, Melbourne. The company describes itself as an Australian medical technology company developing a simple blood test for the early and accurate detection of ovarian cancer.

Its technology is based on a panel of proprietary biomarkers supported by more than 15 years of research and development. Cleo is following a staged strategy that begins with a pre-surgical triage test and extends into recurrence monitoring and population screening. It is conducting the pivotal clinical trial for the triage test, with FDA submission and commercial launch expected in calendar year 2027.

Related Sector Context

Cleo operates in the diagnostics segment of the healthcare sector, where products generally progress through clinical validation, regulatory review and commercialisation.

At 12:04 pm on 23 October 2026 the S&P/ASX 200 was at 8,762.60, down 0.35%, while Cleo shares were higher. The announcement describes ovarian cancer as the most lethal gynaecological cancer, with 51% of patients dying within five years, primarily due to late diagnosis and the lack of effective screening tools.

Risks to Weigh In

The company states that its proof-of-concept results come from a retrospective cohort and require confirmation in larger, independent populations. The company noted that the low-prevalence setting of general population screening is still to be tested.

Cleo's forward-looking statements also acknowledge risks inherent in developing technology and building a business around it. Regulatory review by the FDA, clinical trial outcomes and the timing of any commercial launch remain subject to uncertainty.

Catalysts on Watch

Milestones the announcement identifies include the start of bridging and expanded cohort studies, the evaluation of prospectively collected samples, and publication of the screening development results in peer-reviewed scientific and clinical literature.

For the triage test, the company points to the pivotal clinical trial now under way, an FDA submission planned for early next year, and a commercial launch expected in calendar year 2027.

Where Things Stand

Cleo Diagnostics shares were trading at $0.32, up 4.92%, at 12:04 pm on 23 October 2026, in a session where the S&P/ASX 200 was down 0.35%. The company's most recent update, dated 21 October 2026, reported that its prototype screening test met its pre-defined targets in a 247-person proof-of-concept study, with larger studies and the triage test submission to follow.