Long-Acting FSH Useful for Assisted Reproduction

A new study shows that subfertile women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) to conceive can eliminate the required daily shots of follicle-stimulating hormone (FSH) to induce multiple follicles and instead use long-acting FSH, which offers the benefits of daily FSH without the uncomfortable daily needle sticks.¹

Corifollitropin alfa, a long-acting FSH developed through recombinant DNA technologies, is not yet available in the United States, but it has been available in Europe for several years. A single dose of long-acting FSH is equivalent to 7 days of daily FSH injections.

To compare pregnancy and safety outcomes of long-acting FSH and daily FSH injections, researchers analyzed 4 previous randomized controlled trials that included a total of 2335 women undergoing IVF or ICSI. Of those, 987 women received daily injections of FSH for 1 week and 1348 women had 1 injection of long-acting FSH, which was given at various doses.

The group of women who received the lowest dose of long-acting FSH, 60 to 120 micrograms, had fewer live births than women who received daily FSH. However, live birth rates in women who received slightly higher doses of long-acting FSH, 150 to 180 micrograms, were similar to those in women who received daily injections (343 per 1000 women vs 336 per 1000 women, respectively). In addition, the risks of miscarriage, multiple gestation, ectopic pregnancy, and ovarian hyperstimulation syndrome were similar between FSH treatment types (long-acting vs daily).

The main advantage of the weekly shot of long-acting FSH is convenience. However, many women who use long-acting FSH will still require several daily injections of FSH before their eggs are ready to be harvested. In addition, long-acting FSH should not be used in women who are unlikely to respond to the hormone or in those who may overrespond.

Research on corifollitropin alfa has been submitted to the FDA for review, but its availability in the United States is at least a year or two away, according to Samuel Pang, MD, who was involved in the research that is being reviewed by the FDA.²

Pertinent Point:
- Use of long-acting FSH at medium doses (150 to 180 micrograms) is just as effective as daily FSH and, upon availability in the United States, should be considered a safe treatment option for subfertile women.

References:

1. Pouwer AW, Farquhar C, Kermer JAM. Long-acting FSH versus daily FSH for women undergoing assisted reproduction. Cochrane Database Syst Rev. 2012;6:CD009577.
2. Single hormone shot can replace daily doses in IVF: study. Available at: http://www.reuters.com/article/2012/06/15/health-fertility-idUSL3E8HF00820120615. Accessed July 12, 2012.