Latency is a significant barrier to finding a means to wipe out HIV-1, the virus that causes AIDS. The virus sometimes lies dormant in some cells so that antiviral therapy can only suppress, rather than remove, the infection. To coax HIV-1 out of hiding, scientists have tried administering drugs that attack the virus along with histone deacetylase (HDAC) inhibitors, which promote the transcription of viral genes in latently infected cells. A team led by Ole S. Søgaard of Aarhus University, in Denmark, reports that one HDAC inhibitor called romidepsin—currently used as an anticancer agent in lymphoma patients—has done well in its first HIV proof-of-concept clinical trial (PLOS Pathog. 2015, DOI: 10.1371/journal.ppat.1005142). In five of the six HIV-positive clinical trial participants, the amount of plasma HIV-1 RNA increased, from less than 20 copies of RNA per milliliter to 46 to 103 copies following romidepsin injections. The researchers suggest romidepsin may be a good addition to combination therapies aimed at eradicating HIV-1 in patients. In a new study under way, they are combining romidepsin with a therapeutic HIV vaccine. “Hopefully, this will have a ‘kicking’ and a ‘killing’ component,” Søgaard says.