In short
Nolasiban is an investigational substance being studied to improve the success of in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI). It belongs to a class of medicines called oxytocin receptor antagonists and is taken by mouth. One authorised Phase 2 trial is currently evaluating how two dosing regimens affect uterine contractility in 120 women undergoing fertility treatment.
Key points
- Nolasiban is an oxytocin receptor antagonist being developed to improve IVF and ICSI success rates.
- The current trial is a Phase 2 study in 120 women with an indication for IVF/ICSI.
- It compares two dosing regimens of nolasiban taken by mouth as dispersible tablets.
- The main outcome is the change in uterine contractility index from day 1 to day 4 of treatment.
- The trial is currently authorised but not yet recruiting participants.
- Nolasiban has no marketing authorisation and remains an investigational substance.
What is nolasiban?
Nolasiban (also known as erlosiban, OBE-001, or RPN-002) is an investigational substance classified as a small-molecule oxytocin receptor antagonist. It was originally developed by Merck Serono and is now being developed by ObsEva and ReproNovo. Nolasiban is a chemically synthesised substance and is considered a new molecular entity. In the product records of the current trial, nolasiban has no marketing authorisation and remains an investigational substance supplied by ReproNovo ApS.
How does nolasiban work?
Nolasiban works by blocking the oxytocin receptor. Oxytocin is a hormone that causes the uterus to contract. During embryo transfer in IVF, uterine contractions can reduce the chance that an embryo implants successfully. By blocking oxytocin receptors, nolasiban aims to relax the uterus and reduce contractions, potentially improving the likelihood of pregnancy.
Which conditions is nolasiban studied for?
- Infertility requiring IVF or ICSI — nolasiban is being studied in women who have an indication for assisted reproductive technologies such as in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI).
How is nolasiban given?
Nolasiban is taken by mouth as a dispersible tablet. The current trial uses a dose of 1600 mg given orally. Earlier research evaluated single doses of 900 mg and 1800 mg in healthy volunteers.
What do the clinical trials show?
One authorised Phase 2 trial is currently registered for nolasiban. The trial plans to enrol 120 women with an indication for IVF or ICSI. It is designed to evaluate the pharmacodynamics — that is, the effects of the medicine on the body — of two different dosing regimens of nolasiban.
The main outcome measure is the change in uterine contractility index from day 1 to day 4 of treatment. Uterine contractility describes how strongly and how often the uterus contracts. The trial is currently authorised, meaning it has received approval to proceed but is not yet recruiting participants.
Earlier research in 45 healthy women of child-bearing age found that nolasiban did not cause significant changes in the QT interval, a measurement of the heart's electrical activity. This supports the cardiac safety of nolasiban at the tested doses.
What side effects are known?
A study in 45 healthy female volunteers found no significant effect of nolasiban on the QT interval at doses of 900 mg and 1800 mg, confirming its cardiovascular safety in that setting. The same study also explored relationships between sex hormones and electrocardiogram (ECG) parameters, finding a significant relationship between JTpc and oestradiol, and a negative correlation between heart rate and progesterone. No other side effect information is available from the provided sources.