SAN FRANCISCO — A folate-fortified oral contraceptive significantly improved folate levels in red blood cells and plasma compared with a conventional oral contraceptive after 24 weeks, in a preliminary randomized, double-blind trial of 379 healthy U.S. women seeking contraception.
The study randomized 94 women to take the oral contraceptive Yaz (ethinyl estradiol 0.02 mg plus 3 mg drospirenone) and 285 women to take an experimental version of Yaz that also contained 0.451 mg levomefolate calcium, the calcium salt of L-5-methyltetrahydrofolate, the most prevalent form of dietary folate. During each of six treatment cycles, they got fortified Yaz or conventional Yaz for 24 days, followed by 4 days of levomefolate calcium alone in the fortified group or placebo in the control group.
Seventy women in the control group and 203 in the fortified group completed the 24 weeks of treatment, at which time average red blood cell folate levels were 1,406 nmol/L in the fortified group and 1,024 nmol/L in the control group. Plasma folate levels averaged 61 nmol/L in the fortified group and 41 nmol/L in the control group, Dr. Stephan Bart reported at the meeting.
The differences between groups were statistically significant, said Dr. Bart, a contract researcher at SNBL Clinical Pharmacology Center, Baltimore. Overall rates of adverse events were similar between groups.
The study did not restrict the use of additional folate-containing supplements, and U.S. women generally consume folate-fortified foods, emphasizing that a folate-fortified contraceptive could increase folate levels even in populations already exposed to sources of folate, he noted.
“These results support the concept that folate-fortified oral contraceptives would improve the folate status of all women of childbearing potential,” Dr. Bart said.
Among the women, aged 18-40 years, one or more adverse events were reported in 56% of the fortified group and 57% of the control group. Most adverse events were mild or moderate in intensity and consisted mainly of upper respiratory tract infections (10% of each group) or increases in low-density lipoprotein cholesterol (6% of the fortified group and 9% of the control group), Dr. Bart said.
Disclosures: Bayer Healthcare Pharmaceuticals, which markets Yaz and is developing the folate-fortified version, funded the trial and Dr. Bart's travel to the meeting. His associates in the study all were employees of divisions of Bayer.