Question The Committee is asked the following three questions:
- Does the safety profile of boric acid support its use in parenteral medications intended for neonates ?
- Should the current contraindication for boric acid in the guideline on the excipients in the label and package leaflet of medicinal products for human use remain in its current form ?
- Does the safety profile and clinical experience of boric acid support the establishment of threshold dose levels below which the contraindication should not be labelled ?
Context of the question
The question is asked in the frame of a "Guideline on the excipients in the label and package leaflet of medicinal products for human use" approved by the Pharmaceutical Committee which became applicable from 1st September 1997. According to this guideline, any medicinal product containing boric acid, its salts and esters is contraindicated for infants or young children up to 3 years old.
Assessment
- The Scientific Committee of Medicinal Products and Medical Devices is of the opinion that insufficient information was provided to address fully the questions asked. Additional information is indeed required regarding: (i) the medicinal products for human use that contained boric acid, its salts or esters, prior to the contraindication applicable from 1st September 1997 ; (ii) the benefit for human beings expected from the addition of boric acid, its salts or esters to some medicinal products ; (iii) the scientific data on which was based the contraindication approved by the Pharmaceutical Committee in 1997.
- The missing information precludes any thorough evaluation of risk/benefit, which is essential when considering the possible addition of a chemical entity to medicinal products for human use. Furthermore it is impossible to evaluate possible scenarios of exposure involving, for instance, the simultaneous administration of several medicinal products to the same patient or the misuse of a single medicinal product (such as administration of excessive doses).
- A recent scientific reassessment of boric acid exposure via the oral route indicates that it is possible to propose a maximum tolerated dose of 3 mg/kg/bw for boric acid in children. Therefore, it is proposed that amounts resulting from the manufacture process not exceeding 100 µg/ml can be accepted in vaccines intended for use in neonates and children less than 3 years of age, taking into account their modalities of administration to humans (such as single administrations, ready-for-use formulations).
- Although it is possible to reach this position with respect to vaccines, there are additional questions of broader relevance which the Committee considers can only be answered after the provision of additional information.
References
Craan AG, Myres AW, Green DW (1997) Hazard assessment of boric acid in toys. Regul. Toxicol. Pharmacol. 26, 271-280.