N-(4-Chloro-3-((3-Methyl-2-Butenyl)Oxy)Phenyl)-2-Methyl-3-Furancarbothioamide (also known as UC-781) is a thiocarboxanilide non-nucleoside reverse transcriptase inhibitor patented by Uniroyal Chemical Company, Inc. for prevention of HIV transmission. UC-781 is a potent inhibitor of reverse transcriptase-dependent pyrophosphorolysis, and purportedly restores the chain-terminating activity of zidovudine (AZT) against AZT-resistant virus. In clinical trials single and 7-day topical rectal exposure of UC-781 was safe with no significant adverse events, no detected UC-781 plasma drug levels, no significant mucosal changes, and high participant acceptability. Ex vivo biopsy infections demonstrated marked suppression of HIV infectibility, identifying a potential early biomarker of efficacy.

Aplaviroc (GW873140) is a small-molecule noncompetitive allosteric CCR5 antagonist or HIV entry inhibitor (EI) that binds specifically to human CCR5 and exhibits potent anti-HIV activity in vitro in the nanomolar or subnanomolar range. Aplaviroc has exhibited potent in vivo antiviral activity (1.66 log decrease in viral load at nadir) following 10 days of monotherapy. In vitro studies of antiviral activity demonstrate that aplaviroc is active against HIV isolates from a variety of clades as well as those resistant to current HIV therapies targeting RT, PR, and gp41. However, GlaxoSmithKline has decided to terminate Phase III trials of aplaviroc after encountering additional cases of liver damage in patients taking the drug.

Opaviraline (also known as GW 420867), a nonnucleoside reverse transcriptase inhibitor that was studied for the treatment of HIV infections. The drug participated in clinical trials phase II in Germany, in South Africa, and in the United Kingdom, however, these studies were discontinued.

Netivudine [882C, 882C87, BW 882, Py-araU, Zonavir®] is an orally active thymidine analogue which was being investigated as a treatment for herpes zoster virus infections. Netivudine is a nucleoside analog with potent, specific activity against varicella-zoster virus. It is approximately seven times as potent as acyclovir with an in vitro 50% inhibitory concentration of 1 to 2 uM.

Telinavir (previously known as SC-52151) was developed as an anti-HIV aspartyl protease inhibitor for the treatment of HIV Infections. Telinavir participated in Phase I/II clinical study. In spite of the drug was well tolerated no antiviral activity was produced and further development of the drug was discontinued.

Capravirine (S-1153, AG1549) is a 1,2,4,5-tetrasubstituted imidazole derivative patented by pharmaceutical company Shionogi as specific inhibitors of HIV-​1 reverse transcriptase. However, safety and efficacy studies showed that Capravirine had no specific advantages over currently used NNRTIs. Consequently, clinical trials were discontinued after phase IIb.

Trovirdine [LY 300046, LY 300082, PETT 1] is a NNRT inhibitor of HIV-1 RT, which progressed through Phase II trials for the treatment of HIV infection. Trovirdine inhibits HIV-1 RT with an IC50 of 7 nM. Cell culture experiments demonstrated that LY300046 was a potent inhibitor of the replication of HIV-1 in human T-cell lines and human PBL, including spread of the virus from infected to uninfected T cells. It was potent against patient isolates as well as laboratory isolates of HIV-1 but was not active against HIV-2 or simian immunodeficiency virus.

Brecanavir (previously known as VX-385), a HIV aspartyl protease inhibitor was developed for the treatment of HIV. The inhibition of HIV viral proteinase enzyme prevents cleavage of the gag-pol polyprotein, resulting in noninfectious, immature viral particles. Brecanavir reached Phase II development. However, GlaxoSmithKline announced to discontinue development brecanavir. Because of the inability to develop a viable oral dosage formulation capable of delivering the desired brecanavir levels in patients with multi-drug resistant HIV.

Talviraline (HBY 097) was developed as a nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (NNRTI) for the treatment of HIV Infections. Talviraline participated in a phase II clinical trial. It was found that the drug caused pronounced acute suppression of HIV-1 replication both in combination with zidovudine and alone. However, further development of the drug has been discontinued.

Mozenavir is a non-peptidomimetic, water soluble, cyclic urea that is a selective inhibitor of HIV-1 protease. Mozenavir is active against the virus with the signature D30N nelfinavir resistance-associated mutation and the L90M mutants with decreased susceptibility to a number of other protease inhibitors. In a dose-ranging study assessing Mozenavir, in doses of 750 mg 3 times a day, 1250 mg twice daily, or 1250 mg 3 times a day, compared with standard doses of indinavir, both in combination with lamivudine and stavudine, plasma HIV-1 RNA levels were reduced to below 50 copies/mL in 75% to 80% of patients receiving Mozenavir-based treatment and in 70% of those receiving indinavir-based treatment. Mozenavir-based regimens were generally well tolerated. However, the virus was able to mount considerable resistance against this compound, which was not further developed, also because of poor oral bioavailability in humans and highly variable blood levels.