| Completed | Study of NGX-1998 for the Treatment of Postherpetic Neuralgia Postherpetic Neuralgia, Pain | Phase 2 | 2010-10-01 |
| Completed | Study of NGX-4010 With the Use of Open Label Lidocaine (2.5%)/Prilocaine (2.5%) Cream for the Treatment of Pos Postherpetic Neuralgia | Phase 2 | 2009-06-01 |
| Completed | A Study to Investigate the Tolerability and Effects on Epidermal Nerve Fiber Density of Multiple Low-Concentra Pain | Phase 1 | 2008-06-01 |
| Completed | Study of NGX-4010 for the Treatment of Painful HIV-Associated Neuropathy Pain, HIV Infections, Peripheral Nervous System Diseases | Phase 3 | 2006-06-01 |
| Completed | Study of NGX-4010 for the Treatment of Postherpetic Neuralgia Peripheral Nervous System Diseases, Pain, Neuralgia | Phase 3 | 2006-03-01 |
| Completed | Effect of NGX-4010 on ENFD and Sensory Function Human Volunteers | Phase 1 | 2005-11-01 |
| Completed | Study of NGX-4010 for the Treatment of Painful HIV-Associated Neuropathy (HIV-AN) or Postherpetic Neuralgia (P Herpes Zoster, Neuralgia, Pain | Phase 2 | 2005-08-01 |
| Completed | Study of NGX-4010 for the Treatment of Postherpetic Neuralgia Peripheral Nervous System Diseases, Pain, Neuralgia | Phase 3 | 2005-06-01 |
| Completed | Study of NGX-4010 for the Treatment of Painful HIV-Associated Neuropathy HIV Infections, Peripheral Nervous System Diseases, Pain | Phase 3 | 2003-08-01 |
| Completed | Pilot Study of High-Dose Capsaicin Patches to Treat Postherpetic Neuralgia Pain Neuralgia, Pain, Peripheral Nervous System Diseases | Phase 2 | 2002-03-01 |
| Unknown | Pilot Study of High-Concentration Capsaicin Patches in the Treatment of Painful HIV-Associated Neuropathy HIV Infections | Phase 2 | — |
| Completed | Controlled Study of NGX-4010 for the Treatment of Postherpetic Neuralgia Herpes Zoster, Neuralgia, Pain | Phase 3 | — |
| Terminated | Study of NGX-4010 for Treatment of Painful HIV-Associated Neuropathy HIV Infections, Peripheral Nervous System Diseases, Pain | Phase 3 | — |
| Terminated | An Open-Label Extension Study of NGX-4010 for the Treatment of Neuropathic Pain Herpes Zoster, Neuralgia, Pain | Phase 2 | — |
| Completed | Tolerability of Three Local Anesthetic Formulations in Conjunction With NGX-4010 for the Treatment of Neuropat Herpes Zoster, Neuralgia, Pain | Phase 2 | — |
| Completed | Study of Three Capsaicin Dermal Liquid Formulations on Epidermal Nerve Fiber Immunostaining and Sensory Functi Pain | Phase 1 | — |
| Completed | NGX-4010 for the Treatment of Postherpetic Neuralgia Herpes Zoster, Neuralgia, Pain | Phase 2 / Phase 3 | — |