A team of MIT researchers is currently developing a contraceptive pill to be taken only once a month. Clinical trials may soon be scheduled.
In France, the contraceptive pill is the first contraceptive method. It still has some disadvantages. Side effects – bloating, chest sensitivity, nausea or headache – are an example. Some women also stop taking the pill because they consider this method of contraception binding. It must indeed be taken every day, and even one forgetfulness can increase the chances of getting pregnant.
Starting from this last principle, a team of researchers at MIT, in the United States, is trying to develop a pill that can only be taken once a month. Their work was published in the journal Science Translational Medicine.
A pill in the shape of a starfish
For this study, funded by the Bill & Melinda Gates Foundation, researchers have developed a capsule that, once in the stomach, dissolves and releases a pill in the shape of a starfish.
Inside the six branches of the structure are contained doses of levonorgestrel, the synthetic progestin found in particular in the morning after pill. This method then makes it possible to release the hormones gradually, branch by branch.
One of the main challenges for this work was to develop new polymers that can survive for several days in the highly acidic environment of the stomach. After having tested several in simulated gastric fluid, they finally set their sights on a well-known type of polymer: polyurethane.
Up to 29 days of protection in pigs
For the tests, the researchers turned to pigs. The first tests were very conclusive. Ingested pills protected the animals for an average of 29 days. The researchers found no side effects or obstruction of the digestive system.
Christine Metz, from the Feinstein Institute for Medical Research in New York (USA), found this study very promising. On the other hand, she emphasizes that while pigs are more like humans than mice, they are still very different from a metabolic point of view.
“Pigs have slightly shorter cycles and their rules are different from those of women,” she explains. The mechanisms and timing of food digestion are also very different from those of humans.
However, early clinical trials could be scheduled as early as 2021, the time for researchers “to optimize the materials needed to maintain the dosage form for the desired period and complete release of hormones within the prescribed time,” they write.