An experimental COVID-19 antibody treatment developed by researchers in China has shortened hospital stay of patients based on preliminary results, Sunney Xie, director of the Beijing Advanced Innovation Center for Genomics at Peking University, said on Saturday.

The drug, based on a potent neutralizing antibody DXP-604, has been authorized for compassionate use and delivered to 35 patient at the Beijing Ditan Hospital as of Nov 17, he said during an online academic conference.

Xie, who discovered the antibody with his team, said these patients, with an average age of 53, were either mild or moderate COVID-19 cases.

It took an average of 15 days for them to turn negative in nucleic acid tests and become qualified for being discharged.

That is much shorter than the average hospital stay of 26 days for patients infected with the Delta variant.

However, he said the compassionate use program is not equal to a random, double-blinded trial and more trials are underway to test its efficacy.

Its use also reduced viral load in patients, relieved inflammation and symptoms in respiratory tracts, helped them regain senses of smell and taste, as well as boosted antibodies, Xie said.

In addition to compassionate use tests, he said the Phase 1 clinical trial of the drug had been finished, proving its safety.

Phase 2 trials are underway in China and overseas.

The drug is believed to be capable of tackling all known emerging variants, as well as future mutations based on laboratory results, he said.