Michael Cottrell, 30, and Karl Burge, 28, were jailed for 28 days for contempt of court on Friday after breaking an injunction banning them from picketing the charity in Grays Inn Road, central London.
The two men were involved in a dispute over the trust's links with Wellcome plc, the makers of the Aids drug, AZT. They claim that rather than publicising the debilitating side-effects of AZT, the trust promoted the drug in exchange for funding from Wellcome plc.
Cottrell, who tested positive for HIV in 1985, took AZT for several months but gave up because he felt ill.
The preliminary results of the biggest AZT clinical trial, published in the Lancet in April, found that taking AZT before the onset of Aids was of no benefit. Feeling betrayed, Cottrell began picketing in April. The trust, he said, had produced a 24-page booklet in 1991 with nine pages devoted to AZT; the copyright on the leaflet was held by the Wellcome Foundation, which also paid for the printing.
In May, the Terrence Higgins Trust took out an injunction claiming the protesters were intimidating clients. Cottrell and his partner pleaded guilty, then went back to protest again. A second injunction was taken out and last Friday both men were sentenced to 28 days' jail.
Nick Partridge, the trust's chief executive, denied that it had withheld information about AZT's toxicity. 'Five years ago, activists were complaining that the trust was not doing enough to publicise AZT,' he said.