A research poster was presented at this year’s AAPS, detailing the participation of women in US Food and Drug Administration approved clinical trials between 2000 and 2002.
The research was conducted in part to asses the success of getting more women to participate in clinical trials. For years women were underrepresented in clinical trials, which “resulted in inequality in the understanding, diagnosis and treatment of diseases between the sexes”, according to the study.
In general this problem appears to have been resolved, although Phase I and II trials are still predominately performed on men, as is research for certain products.
For example, trials of cardiovascular drugs contained a high proportion of men, which the researchers believe needs to be resolved by the FDA. This is to ensure the production of safe and effective treatments for cardiovascular ailments, which the research says are the number one cause of mortality, in men and women, in the US.
The researchers also believe that there is room for improvement in the implementation of the FDA’s guidance on monitoring the effect gender has on efficacy, adverse events and pharmacokinetics.
This was recommended by the FDA in guidance issued in 1988 and 1993 but the research suggests that adoption of it has been incomplete. Of the 58 clinical trials investigated the researchers found that 70 per cent had conducted analysis by sex.
Breaking this down into therapeutic fields a third of cardiovascular and renal studies and a quarter of dermatology trials performed analysis by gender. The overall picture has improved but the researchers still think more studies need to adopt this analysis.
Even when differences in a drugs effect on men and women was observed, the labelling did not call for different doses to be administered based on gender. This is part of an ongoing study referred to by the researchers that is looking at sex differences in adverse events.