The contextual penumbra around this revival of As Is, William M. Hoffman’s 1985 play, is almost as vivid as the content of the work itself. It’s billed as “the first AIDS play” – Hoffman wrote it, a programme note explains, “as a sort of therapy” in the early Eighties; a gay man in New York, he was surrounded by dying friends. It was an award-winning hit, transferring to Broadway and coming to London 1987. Yet in the UK, it hadn’t been revived since until 2013, when Andrew Keates staged it at the Finborough.

This is a return of that production – but in the interim, Keates himself has been diagnosed as HIV+. He’s become an active campaigner, and Trafalgar Studios becomes a site for information dispersal. Over 110,000 people in the UK have HIV, the publicity reminds us. Order a drink at the bar, and your hands come to rest naturally on flyers and leaflets from the Terence Higgins Trust’s get tested campaign. There are even free rapid tests after some performances.

All this is a bracingly effective reminder that Aids isn’t yet a thing of the past – although this play very much is. As Is belongs wholly to its moment – a fearful, bewildering one – and the production clearly signposts that this is Eighties New York: the moustaches, the double-denim, the electro-pop.

Rich, a writer with a poetic soul and a promiscuous streak, has left his long-term lover Saul – a photographer, and the stable, sentimental one of the relationship – for a younger model. But when Rich discovers he’s HIV+, the pair reunite, eventually embracing their mutual dependence.

It’s only 80 minutes long, and considering AIDS at this time was a certain death sentence, As Is never really puts you through the wringer. Partly this is down to Hoffman’s lightness of touch as a writer. It’s hardly hold-your-sides stuff, but there are wisecracks, bitchy asides, and gallows humour galore. Which is all to the good: As Is never feels depressingly leaden, even under the weight of 30 years of history.

Steven Webb excels as Rich – he has his own lightness of touch, making the quick-fire changes between lashing rage, sarcastic mockery and neediness believable, but also showing us more than a victim: we see Rich the cocksure cruiser, the pretentious poet, the mischievous lover. His delivery of Hoffman’s sometimes camp dialogue is effortlessly natural.

The interactions between Rich and as his lover Saul – David Poynor – also run the gamut, from neglectfully self-absorbed to rudely spicy to sweetly touching. Poynor’s acting feels a little too large this tiny stage; his widened eyes and restless fidgeting makes Hoffman’s super-fast covering of emotional ground more noticeable. Maybe we’re just a bit British, but blurted bald lines like “I’m very frightened and I miss you” within a few minutes meeting an ex are hard to land convincingly.

Keates’ production has a low-key, busily low-budget air – set is minimal, a few chairs and lockers under neon strips or flashing club lights. The ensemble cast play multiple passing or recurring characters. As Is has a cacophonous quality: a fragmented, polyphonic chorus of voices gabble reactions to Rich’s diagnosis or declaim a litany of dead friends – or of sex acts (the show doesn’t skimp on memories of the “sleazy” freedom they enjoyed pre-AIDS: the orgies, public sex, drug taking, clubbing).

This babble evokes the overwhelming nature of the diagnosis, the fear and paranoia directed towards sufferers at the time, and the panorama of prejudice they faced. Yet scenes can seem designed to cement the play’s status as a sweeping survey of the epidemic: a sufferers’ group features a pregnant woman and a clean-living gay man; tick and tick. The downside to hearing all these voices is that As Is often risks feeling like an ‘issue’ play, frantically hitting each side of this multifaceted topic. Meanwhile recurring characters – a friend, a brother, a lover – inevitably remain pretty sketchy.

Still, the delicate humour and still-raw response to the AIDS crisis makes this a worthy revival, and a quietly moving experience.