§ Mr. Ashleyasked the Secretary of State for Social Services (1) if he will publish in the Official Report the names of the studies considered by the Committee on Safety of Medicines during its recent review of the safety of Debendox; whether the committee had available to it the complete transcript of the recent United States court trial; and, if so, how many copies were available to the committee, and how long it had to study it before it made its recommendation to the Minister on 27 March;
(2) if the studies of Debendox considered recently by the Committee on Safety of Medicines were of a sufficient scale to have provided a reliable indication of whether or not Debendox could be a teratogenic agent carrying the following degrees of risk of danger to the foetus (a) one in 100, (b) one in 500, (c) one in 1,000 and (d) one in 10,000;
(3) if he will publish in the Official Report the total number of women in all the studies of Debendox considered by the Committee on Safety of Medicines that were known to have taken the drug before they were (a) six weeks pregnant and (b) eight weeks pregnant.
§ Dr. VaughanThe Committee on Safety of Medicines in its recent review of Debendox considered a large number of published and unpublished epidemiological and animal teratology studies. The most important of the published studies were as follows:
- Rothman et al. (A J Epidemiol 109: 433 (1979)).
Teratogenicity Testing in Humans: A Method Demonstrating Safety of Bendectin: Smithells R W, Sheppard Shiela (Teratology 17: 31–35 (1978)).Antenatal exposure to doxylamine succinate and dicyclomine hydrochloride (Bendectin) in relation to congenital malformations, perinatal mortality rate, birth weight and intelligence quotient score: Shapiro S et al (Amer J Obstet Gynec 128: 480–85 (1977)).An evaluation of the teratogenicity of certain antinauseant drugs: Milkovich L, van den Berg J (Amer J Obstet Gynec 125: 244–48 (1976)).Morbidity and drugs in pregnancy: Birmingham Research Unit (J R Coll Pract 25: 631 (1975)).A controlled Retrospective Survey in Evaluation of Teratogenicity: Bunde CA and Leyland HM (J New Drugs 5: 193–98 (1965)).598WGeneral Practitioner Clinical Trials Drugs in Pregnancy Survey (Practitioner 191: 775–80 (1963)).Congenital Abnormalities in Children born in Alberta during 1961: A Survey and a Hypotesis: le Van (Canad Med Ass J 89: 120–26 (1963)).An epidemiological study of congenital reduction deformities of the limbs: Smith ESO et al (Brit J of Preventive and Social Medicine 31: 19–41 (1977)).Maternal Drug Histories and Congenital Abnormalities: Greenburg G, Inman WHW et al (BMJ 1977 2: 853–856).The studies provided a substantial amount of scientific evidence on the basis of which the committee felt that it could reach a conclusion. The full transcript of the United States proceedings was not available, but the committee had no reason to believe from the final submissions made in the case that any new first-hand evidence had been presented which the committee had not considered. The committee will continue to monitor published evidence; the secretariat has asked for a complete transcript, which it will study when available and will report further to the committee. It will also keep the committee informed of the nature of any further proceedings in the case concerning the interpretation of the jury's decision.None of the studies considered by the committee demonstrated that the incidence of births of malformed children to mothers who took Debendox was greater than the spontaneous incidence of such births in the United Kingdom or that any specific abnormality was present in these children. Further studies involving very large numbers of women over a period of years would be required to attempt to identify any incidence of risk to the foetus of the sizes mentioned in the right hon. Gentleman's question, and there would be considerable difficulties in assessing the data collated.
The relationship between the drug and possible teratogenesis was investigated at various stages of pregnancy in some of the studies but they contained no uniform statement of gestational age at the time of prescription of the drug which would provide total figures of the number of women who had taken the drug prior to any particular date in their pregnancy.