Pills, gels and implants: Men may get more contraceptives options as WHO floats new guidelines

Men may soon have more contraceptive options beyond condoms and vasectomy, as the World Health Organization (WHO) has released its first global framework for developing new male birth-control methods, a TOI report stated. TheWHO framework sets standards for potential contraceptives such as daily pills and gels, long-acting injections, implants, sperm-function blockers and reversible methods that prevent sperm from being transported. It does not approve any of these methods for public use. Instead, it outlines benchmarks for safety, effectiveness, reversibility, acceptability and affordability.

What the WHO framework covers

The new Target Product Profiles (TPPs) focus on three broad ways of preventing pregnancy. One approach is to reduce sperm production. Another aims to disable sperm functions needed for fertilisation, such as movement. The third seeks to prevent sperm from reaching the reproductive tract by blocking sperm transport.

The proposed products could also differ in how often they need to be used. The framework covers daily tablets or gels, injections that could last three, six or 12 months, and implants designed to work for at least a year. WHO's optimal profile also calls for sperm levels to return to the normal reference range within six months after treatment is stopped.

Male contraceptive researchs

TheWHO move comes as several male contraceptive candidates are being tested in clinical studies. RISUG, or reversible inhibition of sperm under guidance, is one of the methods developed in India. It has completed Phase 1 and Phase 2 studies. Another hydrogel-based method, ADAM, is currently in Phase 1 trials. Researchers are also studying hormonal options. These include nestorone/testosterone gel, dimethandrolone undecanoate (DMAU) and 11β-methyl-19-nortestosterone dodecylcarbonate (11β-MNTDC).

What WHO wants from sperm-suppression methods

For contraceptives that work by reducing sperm production, WHO has specified minimum and optimal targets. Under the minimum target, 90 per cent of men should reach sperm concentrations of 1 million or fewer sperm per millilitre within 12 weeks. The method should also have a cumulative pregnancy rate of no more than 7 per cent over 12 months. The optimal target is more demanding. WHO wants 95 per cent of men to reach the same sperm concentration within eight weeks, while the 12-month pregnancy rate should be 3 per cent or lower. These benchmarks are intended to help researchers assess whether new candidates meet the required performance levels.

Other possible ways to prevent pregnancy

Not every proposed male contraceptive would reduce the amount of sperm produced. Some candidates could leave sperm in the body but prevent them from carrying out functions required for fertilisation. This could include affecting sperm motility or capacitation. Another possibility is to temporarily stop sperm from travelling through the vas deferens. Reversible hydrogels could potentially be used for this purpose. Researchers are also looking at ways to temporarily prevent ejaculation through medication.

What the WHO guidelines mean

The new TPPs are not an announcement that a new male contraceptive is ready for consumers. They provide a common set of standards for researchers, developers and regulators working on these products. With several candidates already in clinical development, the framework is intended to guide future research and help assess potential methods on safety, effectiveness, reversibility, acceptability and cost. The WHO said the field is advancing rapidly, with several candidates in advanced clinical trials.