Phase 2 Clinical Studies

Dicot Pharma's drug candidate LIB-01 is in clinical phase 2. This phase is conducted in patients to study how effective LIB-01 is for treating erectile dysfunction and to further evaluate safety and tolerability.

Phase 2 is divided into 2a and 2b, where the first phase – "Proof of Concept" – aims to show the effect of the study drug in patients and collect information for phase 2b. Phase 2b – "Dose Finding" – aims to determine the dose for the future drug. The dose determined in phase 2b is later used in phase 3.

Dicot Pharma's phase 2a study with LIB-01 for erectile dysfunction was completed in 2025. Below are the overall results presented on October 23, 2025.

Positive results from the phase 2a study with LIB-01 pave the way for continued development

The clinical phase 2a study (NCT06703840) evaluated the safety and efficacy (Proof of Concept) of LIB-01 over eight weeks. The overall results showed that LIB-01 was safe and well-tolerated and provided clinically relevant and long-lasting treatment effects. A combination of patient groups with moderate erectile dysfunction who received LIB-01 in doses of 25 mg and 50 mg showed a significant and clinically relevant average improvement of 6.5 points at 8 weeks compared to placebo (p<0.05). Additionally, a clear dose-response relationship was shown, meaning that the effect increases with a higher dose, which is an important characteristic for a drug candidate and facilitates further clinical development. The study results thus provide a robust basis for conducting the planned clinical phase 2b study with LIB-01.

Dicot Pharma plans to publish the full results in a scientific journal and/or at a scientific conference.

“Looking at the potential implications and impact of LIB-01, there is now even greater evidence that this molecule may dramatically change first-line therapy with the possibility of infrequent dosing, long duration of efficacy and normalization of erectile function, thus obviating the need for on-demand or daily dosing therapy," comments Dr Harin Padma-Nathan, international medical expert in erectile dysfunction, Principal Investigator for Viagra and Cialis.

Purpose of the phase 2a study

• Show that LIB-01 is effective in patients with erectile dysfunction.
• Show that LIB-01 is well-tolerated.
• Provide guiding information on the effect of different doses of the drug candidate for different patient groups and at different times before an upcoming phase 2b study.

Study design

The study included 156 men with erectile dysfunction aged 25–65 years. For inclusion in the study, the established self-assessment questionnaire IIEF-EF was used, where eligible participants had a score of 11-25 (the scale includes scores of 0–30, where scores above 25 equals no erectile dysfunction). The questionnaire measures the severity of erectile dysfunction and has been used in the pivotal studies for the PDE5-inhibiting drugs that have dominated the market since the 90s.

Patients were divided into two study-specific categories based on the severity of dysfunction at the time of inclusion: mild and moderate. Mild dysfunction is found in the range 18–25, while moderate dysfunction is in the range 11–17.

The study evaluated a three-day treatment with LIB-01 in three different doses: 10 mg, 25 mg, and 50 mg, which were compared with a control group that received a placebo. The effect was evaluated with a self-assessment of erectile function, which was documented with the IIEF-EF questionnaire.

The self-assessment was conducted at three time points:

• At study start (baseline), before treatment with LIB-01
• Four weeks after a 3-day treatment with LIB-01
• Eight weeks after a 3-day treatment with LIB-01

The primary endpoint of the study was to evaluate the effect in the full patient population at 4 weeks.

For patients with mild erectile dysfunction, a 2-point improvement is considered clinically relevant, while patients with moderate dysfunction should show an improvement of 5 points.

Summary of results:

In the study, Proof-of-Concept was achieved, as LIB-01 at doses of 25 mg and 50 mg showed a clinically relevant improvement in erectile function according to IIEF-EF after a 3-day oral treatment. This was consistently seen for the entire study population as well as in the study-specific patient groups. Furthermore, the effect of LIB-01 was highest during the first four weeks and was sustained throughout the eight-week study period. The study also provided useful insights on the treatment effect of LIB-01 at different dose levels and showed that LIB-01 is still safe and well-tolerated.

The primary endpoint of the study was to evaluate the effect in the full patient population at 4 weeks, where an improvement in erectile function was seen in all LIB-01 treatment groups. However, the sample size was not large enough to show that the difference in effect between LIB-01 and placebo is statistically significant in the full heterogeneous study population.

A predefined analysis of the effect in each patient group (mild and moderate dysfunction) showed that the two higher doses, 25 and 50 mg, provided clinically relevant improvements and that the effect was sustained over the 8-week study period.

Although both patient groups showed clinically relevant improvements, there were differences between the groups; in the group with mild dysfunction, a ceiling effect (see fact box) was noted, making it difficult to evaluate differences in effect between different dose levels, while this ceiling effect was not seen in the group with moderate dysfunction, and a clear picture of the treatment effect of LIB-01 could be seen.

Noteworthy was:

• A very clear improvement in IIEF-EF score at both week 4 and week 8 for the two higher dose levels.
• The 10 mg dose level did not provide a clinically relevant improvement on IIEF-EF and can thus be seen as a non-therapeutic dose level.
• A dose-response relationship, which reveals a clear pharmacological effect of LIB-01.
• Furthermore, pooling the two higher dose groups in this patient group showed an improvement in IIEF-EF that was both clinically relevant and statistically significant compared to placebo at week 8.

Overall, these results provide a solid basis for the next step in the clinical development program.

Results for the patient group with moderate erectile dysfunction:

Treatment of moderate erectile dysfunction with LIB-01 at doses of 25 mg and 50 mg resulted in clinically relevant effects, while the 10 mg dose did not reach therapeutic level.

Results for the patient group with mild erectile dysfunction:

Treatment of mild erectile dysfunction with LIB-01 at doses of 25 mg and 50 mg resulted in clinically relevant effects, while the 10 mg dose did not reach therapeutic level. In this patient group, a so-called "ceiling effect" (see fact box) was observed, making it difficult to detect differences between dose groups.

Subgroup analyses

Several predefined subgroup analyses have been conducted, one of which is based on pooling the two higher dose groups (25 mg and 50 mg). This was done to evaluate the effect of LIB-01 using a larger sample size, which increases the statistical power of the study.

• When pooling the patient groups with moderate erectile dysfunction who received 25 mg and 50 mg (n=34), an improvement of 7 points was seen at the 4-week and 6.5 points at 8 weeks, the latter showing a statistically significant improvement (p<05) compared to placebo (n=16). (Clinical relevance in this patient group is achieved with a 5-point improvement). See figure below.
• When pooling the patient groups with mild erectile dysfunction who received 25 mg and 50 mg (n=40), an improvement of 4 points was seen at the 4-week and 3.5 points at 8 weeks. (Clinical relevance in this patient group is achieved with a 2-point improvement).

Safety and tolerability

LIB-01 was well tolerated at all dose levels. Side effects were few, mainly mild and transient, and occurred during the first days after administration of LIB-01. The most common adverse reactions were mild and self-limited GI symptoms.

Comment from the CEO

Since we have a completely new approach with a pharmacodynamics that differs from other drugs on the market, this study was designed to give us as much information as possible for future studies. It is therefore very gratifying to see both long-lasting and clear effects, a promising dose-response relationship and a very favorable safety profile. Based on the study results, we now have a robust basis for conducting the planned clinical phase 2b study with LIB-01, and we look forward to the continued development of a long-acting drug candidate with the potential to create a paradigm shift for the treatment of erection problems," says Elin Trampe, CEO of Dicot Pharma.