WHO Technical Report Series, No. 981 - World Health Organization

Quality control – International Reference Materials
EDQM explained that, while it would honour the terms of its contract
with WHO, it could not commit to expanding its responsibility to include the
development of ICRS not explicitly covered by that agreement.
The Expert Committee expressed concern at the possible lack of
compound reference materials. It was suggested that manufacturers and national
pharmacopoeias may be able to assist. The Expert Committee requested the
secretariat to react to the new situation by approaching national pharmacopoeias
to assess what assistance they might provide.
4.1.3 Adoption of established International Chemical Reference Substances
Since the meeting of the Expert Committee in October 2011, EDQM had
established several ICRS and one IIRS. Following a decision of the Expert
Committee in 2010, the secretariat had already provisionally released some of
these ICRS for distribution. These were:
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pyrimethamine ICRS;
erythromycin ethylsuccinate ICRS;
niridazole ICRS;
ciprofloxacin ICRS;
azobenzene melting-point ICRS.
The decisions to release the substances were taken in consultation
with WHO collaborating centres and national control laboratories. The Expert
Committee adopted these ICRS as proposed.
Some reference substances had not been provisionally released, namely:
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atenolol ICRS;
dacarbazine ICRS;
phenobarbital ICRS;
spironolactone ICRS.
This was because the establishment reports were received too late to be
assessed before the meeting of the Expert Committee. These ICRS were adopted,
subject to confirmation by the relevant experts.
In the case of artemisinin the secretariat concluded that it was not possible
to assign a single content to the candidate material that would be suitable for
both assay methods described in The International Pharmacopoeia. The matter
was discussed with selected experts and it was decided to revise the monograph
on artemisinin.
With regard to pentamidine isetionate, it was found during the revision
of the report that the IR spectrum of the candidate material was different
from the IR spectra published in the British Pharmacopoeia and in the Indian
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