Phase of Development: Somatropin is in Phase 2 development as an immune modulator for the treatment of HIV infection. (Somatropin is FDA-approved for the treatment of HIV-associated wasting or cachexia.)
Somatropin is a drug that has been approved by the U.S. Food and Drug Administration (FDA) for various uses, though it is mainly used to treat growth disorders in children and growth hormone deficiency in adults. Somatropin is FDA-approved to treat HIV-associated wasting or cachexia in people with HIV. Off-label use of somatropin may include treatment of HIV-associated lipodystrophy syndrome. As an investigational HIV drug, somatropin belongs to a group of drugs called immune modulators. Immune modulators (also called immunomodulators) are substances that help to activate, boost, or restore normal immune function. Researchers are studying whether somatropin in combination with antiretroviral therapy (ART) can help reduce the latent HIV reservoir. To learn about how investigational drugs are tested during clinical trials, read the AIDSinfo What is an Investigational HIV Drug? and HIV/AIDS Clinical Trials fact sheets.
Which clinical trials are studying somatropin? Study Names: ACTG A5198s; ACTG A5174; NCT00050921 Phase: Not available Status: This study has been completed. Location: United States Purpose: The purpose of this study was to evaluate whether somatropin could increase low CD4 counts in people with HIV who were on ART. Study Name: NCT03091374 Phase: 2 Status: This study is currently recruiting participants. Location: Canada Purpose: The purpose of this study is to evaluate whether somatropin can reduce the latent HIV reservoir in people with HIV on ART with viral suppression. Study Name: NCT00071240 Phase: 2 Status: This study has been completed. Location: United States Purpose: The purpose of this study was to evaluate whether somatropin could increase the size and function of the thymus and increase low CD4 cell counts in people with HIV on ART with viral suppression. Study Names: VIHCREC01; NCT00287677 Phase: 4 Status: This study has been completed. Location: Spain Purpose: The purpose of this study was to evaluate whether somatropin could boost immune responses to three commonly used vaccines in people with HIV on ART with viral suppression. For more details on the studies listed above, see the Health Professional version of this drug summary. The following clinical trials have also evaluated somatropin as an immune modulator: NCT00119769: A Phase 4 substudy that evaluated the effect of somatropin on immune function in people with HIV on ART. NCT01130376: A Phase 1 study that explored whether an investigational called GTU-MultiHIV B boosted with somatropin and other immune modulators could improve immune responses in people with HIV on ART with viral suppression.
What side effects might somatropin cause? What side effects might somatropin cause? One goal of HIV research is to identify new drugs that have fewer side effects. The following side effects were observed in some of the studies of somatropin listed above. Among the 60 participants in this study, eight dropped out because of a side effect. In six participants, carpal tunnel syndrome that was either suspected or diagnosed was likely related to somatropin. One participant entered the study with anal cancer, which worsened during the study, possibly because of somatropin. In this study, three participants stopped taking somatropin and dropped out of the study because of a side effect (diabetes in two participants and carpal tunnel syndrome in one participant). In seven other participants, the somatropin dose was temporarily withheld or reduced by at least half because of side effects. Overall, most of the study participants reported having a side effect that was considered at least moderately severe. Most of the side effects were known effects of somatropin treatment and included joint pain, abnormal glucose metabolism, swelling, and carpal tunnel syndrome. There were three reported cases of lymphoma, but only one occurred in a participant who had received somatropin. Three cases of hand tenosynovitis (inflammation of a tendon and the membrane surrounding the tendon) were reported in participants receiving somatropin. During this study, four participants had their somatropin dose reduced because of a side effect, including joint or muscle pain, swelling of the arms or legs, and nerve damage. In some participants, the somatropin dose had to be reduced at least twice to manage the side effect. Reported side effects in study participants who received somatropin included joint pain, swelling of the hand, muscle pain, nerve damage, carpal tunnel syndrome, weakness, and acute respiratory infection. Although the side effects were generally mild, somatropin treatment was stopped because of carpal tunnel syndrome in one participant and swelling of the hand in another participant. One participant was hospitalized because of acute respiratory infection. Because somatropin is still being studied, information on possible side effects of the drug is not complete. As testing of somatropin continues, additional information on possible side effects will be gathered. Additional information on side effects known to be associated with somatropin can be found in the FDA-approved Full Prescribing Information for Serostim.