Clanobutin sodium review history and regulatory outcomes

Nomination for review

In 1993 the Drugs and Poisons Schedule Standing Committee (DPSSC) noted that there were insufficient residues data to fully assess the possible risks posed to humans from ingestion of residues of clanobutin sodium.

In 1994 the Advisory Committee on Public Health (ACPH) considered clanobutin sodium and noted that no Acceptable Daily Intake (ADI) or Maximum Residue Limits (MRLs) had been set for this compound. The ACPH recommended that it not be used for food-producing animals.

In 1997 the APVMA (formerly the NRA) began a review of clanobutin sodium following advice from the Therapeutic Goods Administration (TGA) about their concerns over the potential risk to the public from long-term exposure to residues in food.

As part of the review the APVMA requested the single registrant, Boehringer Ingelheim Pty Ltd, to provide more information and data to support the continued use and registration of the only clanobutin sodium product on the market, Bykahepar Digestive Stimulant. This data was required to address toxicological concerns and to establish an ADI and MRLs for food-producing animals.

In 1998 the review was suspended as the registrant of Bykahepar Digestive Stimulant indicated that they would not provide the data necessary to complete the residues assessment and that they would not be renewing the registration of their product.

In 1998 the registration of Bykahepar Digestive Stimulant was transferred to another registrant, Schering-Plough, who renewed the registration of the product. At this time the APVMA reactivated the review as the original concerns about residues had not been adequately addressed.

Final review and outcomes

In May 1999 the APVMA completed the review of clanobutin sodium but no final report was released. The APVMA’s key findings of the review were:

• the potential for long term exposure at any level in humans was very low as there was only one registered product for single animal use by injection
• there were insufficient data to support the existing withholding periods (WHP) for clanobutin sodium.

There were insufficient data for the TGA to set an ADI for clanobutin sodium but it was considered that no MRLs needed to be set; with appropriate WHPs, no residues should be detected in the tissues or milk from animals treated with clanobutin.

In the final report the APVMA recommended:

• increasing the WHP for meat from 3 to 28 days for meat and increasing the WHP for milk from nil to 3 days.

The APVMA was satisfied that by varying these conditions of registration, the use of the product could continue.

For more information please contact the Chemical Review Program on (02) 6210 4749 or by email to chemrev@apvma.gov.au