Early Termination of Sildenafil Clinical Trial for Pregnant Women

Overview of Fetal Growth Restriction

A clinical trial investigating the use of sildenafil (commonly known as Viagra) for treating pregnant women with fetal growth restriction was halted prematurely due to fatalities. Severe early-onset fetal growth restriction occurs in approximately 0.4% of pregnancies and often results in premature births, health complications, or, in severe cases, the death of the fetus. Newborns affected by restricted growth and short gestation periods—specifically those born before 28 weeks—face a low survival rate. Even among those who survive, long-term independence during adulthood may be difficult to achieve. This condition may arise partly from issues with uteroplacental blood circulation. According to a 2014 review by Ganzevoort and colleagues published in Systematic Reviews, no proven specific therapies exist for severe fetal growth restriction.

Animal Studies Indicate Potential Benefits

Preliminary animal studies have indicated that sildenafil citrate can enhance pregnancy-related blood flow and improve the birth weight of offspring. These findings, along with smaller studies involving pregnant women, led to the initiation of a trial to explore whether sildenafil could yield similar benefits for women with at-risk fetuses due to severe fetal growth restriction. However, the efficacy of sildenafil as a therapeutic option remains uncertain.

Details of the Clinical Trial

A press release from Reuters, reported by Anthony Deutsch and colleagues, provided insights into a 2015 Dutch clinical trial involving 183 pregnant participants, with approximately half receiving sildenafil. The study aimed to assess potential benefits for fetal development and birth outcomes.

Findings and Outcomes

Tragically, results revealed that among the women treated with Viagra, 11 babies died. Additionally, 17 infants developed lung conditions. In contrast, the control group, which did not receive sildenafil, reported three cases of lung conditions but no fatalities. The trial was stopped immediately due to these alarming outcomes. The suspected cause of death for infants in the Viagra group may be linked to lung issues associated with high blood pressure, suggesting a potential correlation between sildenafil usage and increased lung complications in babies.

Implications for Therapeutics in Pregnancy

This study underscores the limited understanding in the medical field regarding therapeutic options for pregnant women, which may be attributed to the scarcity of studies involving this population. The distressing results highlight the urgent need for further research to uncover beneficial interventions for pregnant women facing challenges with underdeveloped fetuses.

References

– Deutsch A, Kelland K, Hirschler B, and Croft A. Dutch trial with Viagra halted after 11 babies die. Reuters (2018).
– Ganzevoort W et al. STRIDER: Sildenafil therapy in dismal prognosis early-onset intrauterine growth restriction – a protocol for a systematic review with individual participant data and aggregate data meta-analysis and trial sequential analysis. Syst Rev. 2014; 3:23. doi: 10.1186/2046-4053-3-23.