Dr Kwok Wai Him, Chemist at the racing laboratory of the Hong Kong Jockey Club

Dr Kwok Wai Him: ensuring fairness in horse racing

9 October 2017

Dr Kwok Wai Him (Croucher Scholarship, 1997), Racing Chemist at the Hong Kong Jockey Club specialise in doping control within competitive horse racing. Kwok is a Chartered Chemist, Chartered Scientist, member of the Royal Society of Chemistry, and a fellow of the Association of Official Racing Chemists. One of the focuses of his recent research has been in the development of enhanced analytical methods to aid in the detection of peptide-based drugs.

From secondary school, Kwok recalls a natural affinity for the study of chemistry, which soon became a passion. Kwok continued that passion through his school career, receiving his doctorate in the field of chemistry from the Chinese University of Hong Kong. He later undertook post-doctoral studies in the US and New Zealand, working on projects pertaining to organometallics, ligand synthesis and asymmetric catalysis. Today, he utilises his analytical skills in the field of doping control.

“Doping in human sports is certainly a hot topic, and no less so in horse racing. Those wanting to get a competitive edge are making the most of advancements in the fields of biotechnology and molecular biology to identify performance enhancing substances,” Kwok explains. Peptide-based drugs are commonly administered to horses for the purposes of increasing muscle mass or expediting post-race recovery. Advancements in the development of these drugs have enabled simple modifications to the peptides to extend their half-lives and/or enhance their pharmacological effects. The result is more potent and effective drugs.

Doping in human sports is certainly a hot topic, and no less so in horse racing. Those wanting to get a competitive edge are making the most of advancements in the fields of biotechnology and molecular biology to identify performance enhancing substances.

The temptation to utilise these drugs overwhelms some racehorse trainers. Kwok emphasises that ensuring fairness and transparency in the sport, and maintaining the health and well-being of the racehorses is central to his work.

Detecting these peptide-based drugs in routine drug testing is a challenge, largely due to the fact that the elimination of drugs, or detectable drug metabolites in horses, is extremely rapid. Kwok has worked to identify screening targets that remain in horses’ systems for longer periods of time. Once he had discovered such targets, Kwok set about developing a reproducible technique for their detection. The technique utilises a liquid chromatography and high-resolution mass spectrometry [LC-HRMS] method, and focuses primarily on the detection of seven bioactive peptides in horse plasma and urine, at extremely low levels.

Through some modifications to this method, Kwok has increased the number of detectable bioactive peptides to 18. These are: AOD9604, bremelanotide, 3-casomorphin, CJC-1295, dermorphin, desmopressin, GHRP-1, GHRP-2, GHRP-6, hexarelin, hyp-6-dermorphin, ipamorelin, melanotan-2, morphiceptin, N-acetylated LKKTETQ [active ingredient of TB-500), selank, tesamorelin, and triptorelin.

Of the 18 bioactive peptides above, the detection of AOD9604, melanotan-2, and tesamorelin is of particular significance, as Kwok believes that this provides the first valid analytical technique for identifying these particular peptides in horses.

Kwok is driven by an ambition to meet the highest standards of accreditation and be a world-class doping control testing facility. When asked about this mission, he explained, “our laboratory has already acquired a reputation of excellence in drug identification, and we have been working hard to prevent or deter the horse trainers and other licensees to dope in the first place.” As a result, Kwok and his colleagues are well regarded in the industry and they provide analytical and advisory assistance to external regulatory authorities or their laboratories.

As for other noteworthy projects, Kwok and his colleagues have embarked on a different approach to doping control testing. The next step is to investigate alternatives to traditional doping control methodology, based on the identification and monitoring of biomarkers, as opposed to the direct detection of drugs and/or their unique metabolites. It would enable the detection of the presence of multiple drugs of the same class simultaneously, including those that may be new and unknown. In achieving this, Kwok hopes to revolutionise the world of doping control.


Dr Kwok Wai Him works at the racing laboratory of the Hong Kong Jockey Club as Racing Chemist. He received his doctorate from the Chinese University of Hong Kong and undertook post-doctoral training in the USA and New Zealand , working on organometallics, ligand synthesis and asymmetric catalysis. Kwok is a Chartered Chemist, Chartered Scientist, member of the Royal Society of Chemistry, and fellow member of the Association of Official Racing Chemists. He has published over 60 refereed scientific papers, and has given presentations at various international conferences. Kwok has also served as a technical assessor in the area of chemical testing for the Hong Kong Accreditation Service.