TBD Meeting (4123-19)

The first-in-class antiretroviral therapy islatravir (Merck) was well tolerated and had promising efficacy in a phase 2B study including treatment-naive adults with HIV-1 infection, supporting plans to initiate a phase 3 trial, an investigator said at the International AIDS Society Conference on HIV Science.

MattZ90/Thinkstock.com

The proportion of patients achieving viral suppression at week 48 with combinations including the nucleoside transcriptase translocation inhibitor (NRTTI) was comparable to what was achieved with a standard triple regimen, said investigator Jean-Michel Molina, MD, professor of infectious diseases at the University of Paris Diderot, and head of the infectious diseases department at the Saint-Louis Hospital in Paris

The treatment was effective not only as part of a three-drug combination of islatravir, doravirine, and lamivudine over 24 weeks, but also over an additional 24 weeks in patients who achieved viral suppression and were switched to dual therapy with islatravir and doravirine, according to Dr. Molina.

“These are promising data that will encourage the company to move to a phase 3 trial to see how these results can be confirmed in a larger study set, and also to assess the potency of the dual combination for maintenance therapy in the future, providing also novel options for people with a drug that has a high genetic barrier to resistance and efficacy that seems to be quite interesting,” Dr. Molina said in an IAS press conference in Mexico City.

This drug has very potent activity not only against wild-type HIV-1 viruses, but also multiresistant viruses, according to Dr. Molina.

“It has a high inhibitory quotient at a very low dose, so you give people a tiny amount of drug – in the range of 1 milligram per day, instead of a few hundred milligrams with other, regular drugs,” he said.

Another attribute of islatravir is its long half-life of approximately 120 hours, allowing not only for once-daily dosing, but potentially for evaluation as once-weekly or once-monthly dosing in the future, he said, adding that a subdermal islatravir-eluting implant under investigation for preexposure prophylaxis has potential as a once-yearly option.

The international, multicenter, 121-patient clinical trial that Dr. Molina described included adults with HIV-1 infection naive to antiretroviral therapy randomized to islatravir (in one of three doses) plus doravirine and lamivudine, or to the combination of doravirine, lamivudine, and tenofovir (Delstrigo, Merck).

After at least 24 weeks of treatment, subjects in the islatravir treatment groups were transitioned to the two-drug combination of islatravir and doravirine if they had HIV-1 RNA levels less than 50 copies/mL and did not meet any protocol-defined criteria for virologic failure.

Those participants in the islatravir arms who received 48 weeks of treatment had “very good response” and safety that was comparable to the control arm, according to Dr. Molina.

At 48 weeks, the proportion of patients with HIV-1 RNA less than 50 copies/mL were 89.7%, 90%, and 77.4% for regimens containing islatravir 0.25 mg, 0.75 mg, and 2.25 mg, respectively, and 83.9% for those receiving the standard triple therapy, according to reported data.

All patients with protocol-defined virologic failure (greater than or equal to 50 copies/mL) in the study actually had very low viral load, below 80 copies/mL, Dr. Molina said.

The study was supported by Merck. Dr. Molina has been on the Merck advisory board and speaker’s bureau.

SOURCE: Molina J-M et al. IAS 2019, Abstract WEAB0402LB.

The first-in-class antiretroviral therapy islatravir (Merck) was well tolerated and had promising efficacy in a phase 2B study including treatment-naive adults with HIV-1 infection, supporting plans to initiate a phase 3 trial, an investigator said at the International AIDS Society Conference on HIV Science.

MattZ90/Thinkstock.com

The proportion of patients achieving viral suppression at week 48 with combinations including the nucleoside transcriptase translocation inhibitor (NRTTI) was comparable to what was achieved with a standard triple regimen, said investigator Jean-Michel Molina, MD, professor of infectious diseases at the University of Paris Diderot, and head of the infectious diseases department at the Saint-Louis Hospital in Paris

The treatment was effective not only as part of a three-drug combination of islatravir, doravirine, and lamivudine over 24 weeks, but also over an additional 24 weeks in patients who achieved viral suppression and were switched to dual therapy with islatravir and doravirine, according to Dr. Molina.

“These are promising data that will encourage the company to move to a phase 3 trial to see how these results can be confirmed in a larger study set, and also to assess the potency of the dual combination for maintenance therapy in the future, providing also novel options for people with a drug that has a high genetic barrier to resistance and efficacy that seems to be quite interesting,” Dr. Molina said in an IAS press conference in Mexico City.

This drug has very potent activity not only against wild-type HIV-1 viruses, but also multiresistant viruses, according to Dr. Molina.

“It has a high inhibitory quotient at a very low dose, so you give people a tiny amount of drug – in the range of 1 milligram per day, instead of a few hundred milligrams with other, regular drugs,” he said.

Another attribute of islatravir is its long half-life of approximately 120 hours, allowing not only for once-daily dosing, but potentially for evaluation as once-weekly or once-monthly dosing in the future, he said, adding that a subdermal islatravir-eluting implant under investigation for preexposure prophylaxis has potential as a once-yearly option.

The international, multicenter, 121-patient clinical trial that Dr. Molina described included adults with HIV-1 infection naive to antiretroviral therapy randomized to islatravir (in one of three doses) plus doravirine and lamivudine, or to the combination of doravirine, lamivudine, and tenofovir (Delstrigo, Merck).

After at least 24 weeks of treatment, subjects in the islatravir treatment groups were transitioned to the two-drug combination of islatravir and doravirine if they had HIV-1 RNA levels less than 50 copies/mL and did not meet any protocol-defined criteria for virologic failure.

Those participants in the islatravir arms who received 48 weeks of treatment had “very good response” and safety that was comparable to the control arm, according to Dr. Molina.

At 48 weeks, the proportion of patients with HIV-1 RNA less than 50 copies/mL were 89.7%, 90%, and 77.4% for regimens containing islatravir 0.25 mg, 0.75 mg, and 2.25 mg, respectively, and 83.9% for those receiving the standard triple therapy, according to reported data.

All patients with protocol-defined virologic failure (greater than or equal to 50 copies/mL) in the study actually had very low viral load, below 80 copies/mL, Dr. Molina said.

The study was supported by Merck. Dr. Molina has been on the Merck advisory board and speaker’s bureau.

SOURCE: Molina J-M et al. IAS 2019, Abstract WEAB0402LB.

The first-in-class antiretroviral therapy islatravir (Merck) was well tolerated and had promising efficacy in a phase 2B study including treatment-naive adults with HIV-1 infection, supporting plans to initiate a phase 3 trial, an investigator said at the International AIDS Society Conference on HIV Science.

MattZ90/Thinkstock.com

The proportion of patients achieving viral suppression at week 48 with combinations including the nucleoside transcriptase translocation inhibitor (NRTTI) was comparable to what was achieved with a standard triple regimen, said investigator Jean-Michel Molina, MD, professor of infectious diseases at the University of Paris Diderot, and head of the infectious diseases department at the Saint-Louis Hospital in Paris

The treatment was effective not only as part of a three-drug combination of islatravir, doravirine, and lamivudine over 24 weeks, but also over an additional 24 weeks in patients who achieved viral suppression and were switched to dual therapy with islatravir and doravirine, according to Dr. Molina.

“These are promising data that will encourage the company to move to a phase 3 trial to see how these results can be confirmed in a larger study set, and also to assess the potency of the dual combination for maintenance therapy in the future, providing also novel options for people with a drug that has a high genetic barrier to resistance and efficacy that seems to be quite interesting,” Dr. Molina said in an IAS press conference in Mexico City.

This drug has very potent activity not only against wild-type HIV-1 viruses, but also multiresistant viruses, according to Dr. Molina.

“It has a high inhibitory quotient at a very low dose, so you give people a tiny amount of drug – in the range of 1 milligram per day, instead of a few hundred milligrams with other, regular drugs,” he said.

Another attribute of islatravir is its long half-life of approximately 120 hours, allowing not only for once-daily dosing, but potentially for evaluation as once-weekly or once-monthly dosing in the future, he said, adding that a subdermal islatravir-eluting implant under investigation for preexposure prophylaxis has potential as a once-yearly option.

The international, multicenter, 121-patient clinical trial that Dr. Molina described included adults with HIV-1 infection naive to antiretroviral therapy randomized to islatravir (in one of three doses) plus doravirine and lamivudine, or to the combination of doravirine, lamivudine, and tenofovir (Delstrigo, Merck).

After at least 24 weeks of treatment, subjects in the islatravir treatment groups were transitioned to the two-drug combination of islatravir and doravirine if they had HIV-1 RNA levels less than 50 copies/mL and did not meet any protocol-defined criteria for virologic failure.

Those participants in the islatravir arms who received 48 weeks of treatment had “very good response” and safety that was comparable to the control arm, according to Dr. Molina.

At 48 weeks, the proportion of patients with HIV-1 RNA less than 50 copies/mL were 89.7%, 90%, and 77.4% for regimens containing islatravir 0.25 mg, 0.75 mg, and 2.25 mg, respectively, and 83.9% for those receiving the standard triple therapy, according to reported data.

All patients with protocol-defined virologic failure (greater than or equal to 50 copies/mL) in the study actually had very low viral load, below 80 copies/mL, Dr. Molina said.

The study was supported by Merck. Dr. Molina has been on the Merck advisory board and speaker’s bureau.

SOURCE: Molina J-M et al. IAS 2019, Abstract WEAB0402LB.

An implant that elutes an investigational antiretroviral agent provided drug release that should be sufficient for HIV prophylaxis for 12 months or more, according to results of a phase 1 clinical trial just presented here at the International AIDS Society Conference on HIV Science.

grandeduc/Thinkstock

The islatravir-eluting arm implant was safe and generally well tolerated, with drug concentrations that remained above the target level needed for protection throughout the randomized, placebo-controlled study, said investigator Randolph P. Matthews, MD, PhD, senior principal scientist at Merck, Kenilworth, N.J.

“Based on this study, the islatravir-eluting implant appears to be a potentially important option for preexposure prophylaxis (PrEP) as an agent that could be effective with yearly dosing,” Dr. Matthews said in an IAS press conference.

This drug-eluting implant, inserted subdermally in the skin of the upper arm, could represent a “meaningful option” for many individuals at high risk of HIV infection, particularly those who have adherence challenges, said Dr. Matthews.

“Many at-risk individuals face adherence challenges with the existing daily oral PrEP therapy,” he added. “A high degree of adherence is required for it to be effective, and daily adherence is challenging for many, particularly for women.”

Islatravir, formerly known as MK-8591, is a nucleoside reverse transcriptase translocation inhibitor (NRTTI) being evaluated in clinical trials not only for PrEP, but also for treatment of HIV-1 infection in combination with other antiretrovirals.

In preclinical trials, islatravir demonstrated high potency, a high barrier to resistance, and a long half-life, according to Dr. Matthews.

The phase 1, single-site, double-blind study included a total of 16 healthy adult volunteers who received implants of islatravir at one of two doses (54 mg and 62 mg) or placebo for 12 weeks.

Both active doses of islatravir led to concentrations above the target level at 12 weeks, and based on data modeling, the higher-dose implant would still be above the target level for at least a year, Dr. Matthews said in the press conference.

The projected duration above the target ranged from 12 to 16 months for the 62-mg dose of islatravir, and from 8 to 10 months for the 54-mg dose, according to the reported data.

All drug-related adverse events were mild or moderate in severity, and none of the volunteers discontinued the study because of an adverse event, Dr. Matthews said.

Taken together, these data support the continued progression of the implant clinical development program, said Dr. Matthews, who is an employee of Merck, which sponsored the study.

SOURCE: Matthews RP et al. IAS 2019, Abstract TUAC0401LB.

An implant that elutes an investigational antiretroviral agent provided drug release that should be sufficient for HIV prophylaxis for 12 months or more, according to results of a phase 1 clinical trial just presented here at the International AIDS Society Conference on HIV Science.

grandeduc/Thinkstock

The islatravir-eluting arm implant was safe and generally well tolerated, with drug concentrations that remained above the target level needed for protection throughout the randomized, placebo-controlled study, said investigator Randolph P. Matthews, MD, PhD, senior principal scientist at Merck, Kenilworth, N.J.

“Based on this study, the islatravir-eluting implant appears to be a potentially important option for preexposure prophylaxis (PrEP) as an agent that could be effective with yearly dosing,” Dr. Matthews said in an IAS press conference.

This drug-eluting implant, inserted subdermally in the skin of the upper arm, could represent a “meaningful option” for many individuals at high risk of HIV infection, particularly those who have adherence challenges, said Dr. Matthews.

“Many at-risk individuals face adherence challenges with the existing daily oral PrEP therapy,” he added. “A high degree of adherence is required for it to be effective, and daily adherence is challenging for many, particularly for women.”

Islatravir, formerly known as MK-8591, is a nucleoside reverse transcriptase translocation inhibitor (NRTTI) being evaluated in clinical trials not only for PrEP, but also for treatment of HIV-1 infection in combination with other antiretrovirals.

In preclinical trials, islatravir demonstrated high potency, a high barrier to resistance, and a long half-life, according to Dr. Matthews.

The phase 1, single-site, double-blind study included a total of 16 healthy adult volunteers who received implants of islatravir at one of two doses (54 mg and 62 mg) or placebo for 12 weeks.

Both active doses of islatravir led to concentrations above the target level at 12 weeks, and based on data modeling, the higher-dose implant would still be above the target level for at least a year, Dr. Matthews said in the press conference.

The projected duration above the target ranged from 12 to 16 months for the 62-mg dose of islatravir, and from 8 to 10 months for the 54-mg dose, according to the reported data.

All drug-related adverse events were mild or moderate in severity, and none of the volunteers discontinued the study because of an adverse event, Dr. Matthews said.

Taken together, these data support the continued progression of the implant clinical development program, said Dr. Matthews, who is an employee of Merck, which sponsored the study.

SOURCE: Matthews RP et al. IAS 2019, Abstract TUAC0401LB.

An implant that elutes an investigational antiretroviral agent provided drug release that should be sufficient for HIV prophylaxis for 12 months or more, according to results of a phase 1 clinical trial just presented here at the International AIDS Society Conference on HIV Science.

grandeduc/Thinkstock

The islatravir-eluting arm implant was safe and generally well tolerated, with drug concentrations that remained above the target level needed for protection throughout the randomized, placebo-controlled study, said investigator Randolph P. Matthews, MD, PhD, senior principal scientist at Merck, Kenilworth, N.J.

“Based on this study, the islatravir-eluting implant appears to be a potentially important option for preexposure prophylaxis (PrEP) as an agent that could be effective with yearly dosing,” Dr. Matthews said in an IAS press conference.

This drug-eluting implant, inserted subdermally in the skin of the upper arm, could represent a “meaningful option” for many individuals at high risk of HIV infection, particularly those who have adherence challenges, said Dr. Matthews.

“Many at-risk individuals face adherence challenges with the existing daily oral PrEP therapy,” he added. “A high degree of adherence is required for it to be effective, and daily adherence is challenging for many, particularly for women.”

Islatravir, formerly known as MK-8591, is a nucleoside reverse transcriptase translocation inhibitor (NRTTI) being evaluated in clinical trials not only for PrEP, but also for treatment of HIV-1 infection in combination with other antiretrovirals.

In preclinical trials, islatravir demonstrated high potency, a high barrier to resistance, and a long half-life, according to Dr. Matthews.

The phase 1, single-site, double-blind study included a total of 16 healthy adult volunteers who received implants of islatravir at one of two doses (54 mg and 62 mg) or placebo for 12 weeks.

Both active doses of islatravir led to concentrations above the target level at 12 weeks, and based on data modeling, the higher-dose implant would still be above the target level for at least a year, Dr. Matthews said in the press conference.

The projected duration above the target ranged from 12 to 16 months for the 62-mg dose of islatravir, and from 8 to 10 months for the 54-mg dose, according to the reported data.

All drug-related adverse events were mild or moderate in severity, and none of the volunteers discontinued the study because of an adverse event, Dr. Matthews said.

Taken together, these data support the continued progression of the implant clinical development program, said Dr. Matthews, who is an employee of Merck, which sponsored the study.

SOURCE: Matthews RP et al. IAS 2019, Abstract TUAC0401LB.

New studies of a two-drug, integrase inhibitor–based regimen, presented at the International AIDS Society Conference on HIV Science, provide additional data to challenge the three-drug HIV treatment paradigm.

In the results of one study, known as TANGO (NCT03446573), switching to the fixed-dose combination of dolutegravir (DTG) plus lamivudine (3TC) from a tenofovir alafenamide (TAF)–based three- or four-drug regimen maintained virologic suppression at 48 weeks in HIV-1 infected adults, an investigator said, and was noninferior to continuing TAF-based therapy.

In another presentation, updating results of the GEMINI-1 (NCT02831673) and GEMINI-2 studies (NCT02831764), a researcher said the DTG+3TC combination remained noninferior to DTG plus tenofovir/emtricitabine (TDF/FTC) at week 96 in antiretroviral (ART) treatment-naive adults with HIV-1 infection, with no treatment-emergent resistance and no increase in risk of virologic failure.

In light of these findings and encouraging findings from studies of other two-drug regimens, it may be time to “rethink the position of dual therapy in the international guidelines,” according to IAS Past President Pedro Cahn, MD, PhD, of Fundación Huésped, Buenos Aires, who presented the updated GEMINI study results.

“We don’t mean to say now everything should be dual therapy, and we are going to wipe out all other options, but I think we have another strong option for initiating therapy, and probably also for switch therapy,” Dr. Cahn said in a press conference.

Dr. Cahn presented an updated analysis of GEMINI-1 and GEMINI-2, two identically designed phase 3 randomized clinical trials including a total of 1,400 patients.

The 48-week results from those trials, presented in 2018, showed for the first time that a dual-therapy combination of an integrase inhibitor with 3TC was noninferior to the triple-drug regimen of DTG+TDF/FTC, Dr. Cahn said.

In the updated analysis, including 96 weeks of data, the two-drug regimen remained noninferior to the three-drug regimen, according to the investigator.

A total of 11 patients on DTG+3TC and 7 on DTG+TDF/FTC met virologic withdrawal criteria through week 96, with no treatment-emergent resistance mutations seen in either arm, according to results reported in the study abstract.

The proportion of subjects with plasma HIV-1 RNA below 50 c/mL at week 96 was 86% for the two-drug regimen and 90% for the three-drug regimen (adjusted difference, –3.4; 95% confidence interval, –6.7 to 0.0), the reported data showed.

Drug-related adverse events were numerically more common in the three-drug arm, though rates of adverse event–related withdrawal were low in both arms, according to investigators.

The strategy of switching to DTG+3TC was evaluated in the randomized, phase 3 TANGO trial, which included 741 subjects who were already virally suppressed on a TAF-based three- or four-drug regimen. After 48 weeks of therapy, the two-drug regimen was noninferior to remaining on TAF-based therapy in terms of achieving and maintaining viral suppression, according to investigator Jean van Wyk, MB, ChB, Global Medical Lead for dolutegravir at ViiV Healthcare.

Safety outcomes were similar between the arms, though the absolute number of treatment-related adverse events was higher in the DTG+3TC arm “as expected in a switch study,” Dr. van Wyk said.

The percentage of subjects withdrawing from the study because of adverse events was 4% in the DTG+3TC arm and less than 1% in the TAF-based treatment arm, according to reported data.

And with regard to safety there were similar outcomes between the two arms, with regard to overall adverse events, “but as expected in a switch study, we did see more treatment-related adverse events in the dolutegravir plus lamivudine arm, and that’s because the majority of patients were on two new agents in the form of dolutegravir plus lamivudine, so it’s completely expected,” Dr. van Wyk said.

The study met its primary endpoint for noninferiority at week 48, based on the Food and Drug Administration snapshot algorithm. Results showed that switching to DTG+3TC was noninferior to continuing the TAF-containing regimen at week 48, with virologic failure per snapshot criteria seen in less than 1% of subjects in either arm, according to reported data. The proportion of subjects with plasma HIV-1 RNA less than 50 c/mL was 93.2% and 93.0% for the DTG+3TC and TAF-based treatment arms, respectively.

Longer-term follow-up will be important to confirm the noninferiority of the two-drug approach, Dr. van Wyk and Dr. Cahn said in the press conference. The TANGO study of the switch strategy will continue through 148 weeks, while an additional year of follow-up is ongoing for the GEMINI studies of the initial therapy approach.

TANGO and both GEMINI 1 and GEMINI 2 were sponsored by ViiV Healthcare. Dr. van Wyk is an employee of ViiV Healthcare. Dr. Cahn has received research support grants, and fees as consultant and speaker from ViiV Healthcare.

SOURCE: Cahn P et al. IAS 2019, Abstract WEAB0404LB; van Wyk J et al. IAS 2019, Abstract WEAB0403LB.

New studies of a two-drug, integrase inhibitor–based regimen, presented at the International AIDS Society Conference on HIV Science, provide additional data to challenge the three-drug HIV treatment paradigm.

In the results of one study, known as TANGO (NCT03446573), switching to the fixed-dose combination of dolutegravir (DTG) plus lamivudine (3TC) from a tenofovir alafenamide (TAF)–based three- or four-drug regimen maintained virologic suppression at 48 weeks in HIV-1 infected adults, an investigator said, and was noninferior to continuing TAF-based therapy.

In another presentation, updating results of the GEMINI-1 (NCT02831673) and GEMINI-2 studies (NCT02831764), a researcher said the DTG+3TC combination remained noninferior to DTG plus tenofovir/emtricitabine (TDF/FTC) at week 96 in antiretroviral (ART) treatment-naive adults with HIV-1 infection, with no treatment-emergent resistance and no increase in risk of virologic failure.

In light of these findings and encouraging findings from studies of other two-drug regimens, it may be time to “rethink the position of dual therapy in the international guidelines,” according to IAS Past President Pedro Cahn, MD, PhD, of Fundación Huésped, Buenos Aires, who presented the updated GEMINI study results.

“We don’t mean to say now everything should be dual therapy, and we are going to wipe out all other options, but I think we have another strong option for initiating therapy, and probably also for switch therapy,” Dr. Cahn said in a press conference.

Dr. Cahn presented an updated analysis of GEMINI-1 and GEMINI-2, two identically designed phase 3 randomized clinical trials including a total of 1,400 patients.

The 48-week results from those trials, presented in 2018, showed for the first time that a dual-therapy combination of an integrase inhibitor with 3TC was noninferior to the triple-drug regimen of DTG+TDF/FTC, Dr. Cahn said.

In the updated analysis, including 96 weeks of data, the two-drug regimen remained noninferior to the three-drug regimen, according to the investigator.

A total of 11 patients on DTG+3TC and 7 on DTG+TDF/FTC met virologic withdrawal criteria through week 96, with no treatment-emergent resistance mutations seen in either arm, according to results reported in the study abstract.

The proportion of subjects with plasma HIV-1 RNA below 50 c/mL at week 96 was 86% for the two-drug regimen and 90% for the three-drug regimen (adjusted difference, –3.4; 95% confidence interval, –6.7 to 0.0), the reported data showed.

Drug-related adverse events were numerically more common in the three-drug arm, though rates of adverse event–related withdrawal were low in both arms, according to investigators.

The strategy of switching to DTG+3TC was evaluated in the randomized, phase 3 TANGO trial, which included 741 subjects who were already virally suppressed on a TAF-based three- or four-drug regimen. After 48 weeks of therapy, the two-drug regimen was noninferior to remaining on TAF-based therapy in terms of achieving and maintaining viral suppression, according to investigator Jean van Wyk, MB, ChB, Global Medical Lead for dolutegravir at ViiV Healthcare.

Safety outcomes were similar between the arms, though the absolute number of treatment-related adverse events was higher in the DTG+3TC arm “as expected in a switch study,” Dr. van Wyk said.

The percentage of subjects withdrawing from the study because of adverse events was 4% in the DTG+3TC arm and less than 1% in the TAF-based treatment arm, according to reported data.

And with regard to safety there were similar outcomes between the two arms, with regard to overall adverse events, “but as expected in a switch study, we did see more treatment-related adverse events in the dolutegravir plus lamivudine arm, and that’s because the majority of patients were on two new agents in the form of dolutegravir plus lamivudine, so it’s completely expected,” Dr. van Wyk said.

The study met its primary endpoint for noninferiority at week 48, based on the Food and Drug Administration snapshot algorithm. Results showed that switching to DTG+3TC was noninferior to continuing the TAF-containing regimen at week 48, with virologic failure per snapshot criteria seen in less than 1% of subjects in either arm, according to reported data. The proportion of subjects with plasma HIV-1 RNA less than 50 c/mL was 93.2% and 93.0% for the DTG+3TC and TAF-based treatment arms, respectively.

Longer-term follow-up will be important to confirm the noninferiority of the two-drug approach, Dr. van Wyk and Dr. Cahn said in the press conference. The TANGO study of the switch strategy will continue through 148 weeks, while an additional year of follow-up is ongoing for the GEMINI studies of the initial therapy approach.

TANGO and both GEMINI 1 and GEMINI 2 were sponsored by ViiV Healthcare. Dr. van Wyk is an employee of ViiV Healthcare. Dr. Cahn has received research support grants, and fees as consultant and speaker from ViiV Healthcare.

SOURCE: Cahn P et al. IAS 2019, Abstract WEAB0404LB; van Wyk J et al. IAS 2019, Abstract WEAB0403LB.

New studies of a two-drug, integrase inhibitor–based regimen, presented at the International AIDS Society Conference on HIV Science, provide additional data to challenge the three-drug HIV treatment paradigm.

In the results of one study, known as TANGO (NCT03446573), switching to the fixed-dose combination of dolutegravir (DTG) plus lamivudine (3TC) from a tenofovir alafenamide (TAF)–based three- or four-drug regimen maintained virologic suppression at 48 weeks in HIV-1 infected adults, an investigator said, and was noninferior to continuing TAF-based therapy.

In another presentation, updating results of the GEMINI-1 (NCT02831673) and GEMINI-2 studies (NCT02831764), a researcher said the DTG+3TC combination remained noninferior to DTG plus tenofovir/emtricitabine (TDF/FTC) at week 96 in antiretroviral (ART) treatment-naive adults with HIV-1 infection, with no treatment-emergent resistance and no increase in risk of virologic failure.

In light of these findings and encouraging findings from studies of other two-drug regimens, it may be time to “rethink the position of dual therapy in the international guidelines,” according to IAS Past President Pedro Cahn, MD, PhD, of Fundación Huésped, Buenos Aires, who presented the updated GEMINI study results.

“We don’t mean to say now everything should be dual therapy, and we are going to wipe out all other options, but I think we have another strong option for initiating therapy, and probably also for switch therapy,” Dr. Cahn said in a press conference.

Dr. Cahn presented an updated analysis of GEMINI-1 and GEMINI-2, two identically designed phase 3 randomized clinical trials including a total of 1,400 patients.

The 48-week results from those trials, presented in 2018, showed for the first time that a dual-therapy combination of an integrase inhibitor with 3TC was noninferior to the triple-drug regimen of DTG+TDF/FTC, Dr. Cahn said.

In the updated analysis, including 96 weeks of data, the two-drug regimen remained noninferior to the three-drug regimen, according to the investigator.

A total of 11 patients on DTG+3TC and 7 on DTG+TDF/FTC met virologic withdrawal criteria through week 96, with no treatment-emergent resistance mutations seen in either arm, according to results reported in the study abstract.

The proportion of subjects with plasma HIV-1 RNA below 50 c/mL at week 96 was 86% for the two-drug regimen and 90% for the three-drug regimen (adjusted difference, –3.4; 95% confidence interval, –6.7 to 0.0), the reported data showed.

Drug-related adverse events were numerically more common in the three-drug arm, though rates of adverse event–related withdrawal were low in both arms, according to investigators.

The strategy of switching to DTG+3TC was evaluated in the randomized, phase 3 TANGO trial, which included 741 subjects who were already virally suppressed on a TAF-based three- or four-drug regimen. After 48 weeks of therapy, the two-drug regimen was noninferior to remaining on TAF-based therapy in terms of achieving and maintaining viral suppression, according to investigator Jean van Wyk, MB, ChB, Global Medical Lead for dolutegravir at ViiV Healthcare.

Safety outcomes were similar between the arms, though the absolute number of treatment-related adverse events was higher in the DTG+3TC arm “as expected in a switch study,” Dr. van Wyk said.

The percentage of subjects withdrawing from the study because of adverse events was 4% in the DTG+3TC arm and less than 1% in the TAF-based treatment arm, according to reported data.

And with regard to safety there were similar outcomes between the two arms, with regard to overall adverse events, “but as expected in a switch study, we did see more treatment-related adverse events in the dolutegravir plus lamivudine arm, and that’s because the majority of patients were on two new agents in the form of dolutegravir plus lamivudine, so it’s completely expected,” Dr. van Wyk said.

The study met its primary endpoint for noninferiority at week 48, based on the Food and Drug Administration snapshot algorithm. Results showed that switching to DTG+3TC was noninferior to continuing the TAF-containing regimen at week 48, with virologic failure per snapshot criteria seen in less than 1% of subjects in either arm, according to reported data. The proportion of subjects with plasma HIV-1 RNA less than 50 c/mL was 93.2% and 93.0% for the DTG+3TC and TAF-based treatment arms, respectively.

Longer-term follow-up will be important to confirm the noninferiority of the two-drug approach, Dr. van Wyk and Dr. Cahn said in the press conference. The TANGO study of the switch strategy will continue through 148 weeks, while an additional year of follow-up is ongoing for the GEMINI studies of the initial therapy approach.

TANGO and both GEMINI 1 and GEMINI 2 were sponsored by ViiV Healthcare. Dr. van Wyk is an employee of ViiV Healthcare. Dr. Cahn has received research support grants, and fees as consultant and speaker from ViiV Healthcare.

SOURCE: Cahn P et al. IAS 2019, Abstract WEAB0404LB; van Wyk J et al. IAS 2019, Abstract WEAB0403LB.

The risk of neural tube defects linked to dolutegravir exposure during pregnancy is lower than previously signaled, according to new reports that have prompted the World Health Organization (WHO) to confirm that this antiviral medication should be the preferred option across all populations.

alexskopje/Thinkstock

The use of dolutegravir (DTG) during pregnancy has been a pressing global health question since May 2018, when an unplanned interim analysis of the Tsepamo surveillance study of birth outcomes in Botswana showed four neural tube defects associated with dolutegravir exposure among 426 infants born to HIV-positive women (0.94%).

With follow-up for additional births, however, just one more neural tube defect was identified out of 1,683 deliveries among women who had taken DTG around the time of conception (0.30%), according to a report just presented here at the at the International AIDS Society Conference on HIV Science.

By comparison, prevalence rates of neural tube defects were 0.10% for mothers taking other antiretroviral therapies at conception, 0.04% for those specifically taking efavirenz at conception, and 0.08% in HIV-uninfected mothers, according to the report, which was simultaneously published in the New England Journal of Medicine.

“While there may be a risk for neural tube defects, this risk is small, and really importantly, needs to be weighed against the large potential benefits of dolutegravir,” investigator Rebecca M. Zash, MD, of Beth Israel Deaconess Medical Center, Boston, said here in Mexico City during an IAS 2019 video press conference.

The WHO had previously sounded a note of caution, saying that DTG could be “considered” in women of childbearing age if other first‐line antiretroviral agents such as efavirenz could not be used.

However, following release of new evidence, including the study by Dr. Zash and colleagues, the WHO has come out with a clear recommendation for HIV drug as “the preferred first-line and second-line treatment for all populations, including pregnant women and those of childbearing potential.”

The updated scientific reports and guidelines have important implications for global health. “Many countries have been working to make dolutegravir-based treatment their preferred first-line regimen, as it’s got several advantages over efavirenz, which people have been using for many years now, including its tolerability and resistance profiles, and its impact on morbidity and mortality,” IAS president Anton Pozniak, MD, said in the press conference.

Some countries paused their plans to roll out dolutegravir-based regimens after the preliminary safety signal from the Tsepamo study was reported, Dr. Pozniak added.

In another study presented at IAS looking at dolutegravir use at conception, investigators described an additional surveillance study in Botswana, conducted independently from the Tsepamo study. One neural tube defect was found among 152 deliveries in mothers who had been taking DTG at conception (0.66%), and two neural tube defects among 2,326 deliveries to HIV-negative mothers (0.09%).

Although the number of deliveries are small in this study, the results suggest a risk of neural tube defects with DTG exposure at conception of less than 1%, said Mmakgomo Mimi Raesima, MD, MPH, public health specialist, Ministry of Health and Wellness, Botswana.

Because neural-tube defects might be related to low folate levels, Dr. Raesima said “conversations are continuing” with regard to folate food fortification in Botswana, a country that does not mandate folate-fortified grains.

“We want to capitalize on the momentum from these results,” Dr. Raesima said in the press conference.

The Tsepamo study was funded by the National Institutes of Health. Dr. Zash reported grants during the conduct of the study from the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

SOURCE: Zash R et al. N Engl J Med. 2019 Jul 22. doi: 10.1056/NEJMoa1905230.

The risk of neural tube defects linked to dolutegravir exposure during pregnancy is lower than previously signaled, according to new reports that have prompted the World Health Organization (WHO) to confirm that this antiviral medication should be the preferred option across all populations.

alexskopje/Thinkstock

The use of dolutegravir (DTG) during pregnancy has been a pressing global health question since May 2018, when an unplanned interim analysis of the Tsepamo surveillance study of birth outcomes in Botswana showed four neural tube defects associated with dolutegravir exposure among 426 infants born to HIV-positive women (0.94%).

With follow-up for additional births, however, just one more neural tube defect was identified out of 1,683 deliveries among women who had taken DTG around the time of conception (0.30%), according to a report just presented here at the at the International AIDS Society Conference on HIV Science.

By comparison, prevalence rates of neural tube defects were 0.10% for mothers taking other antiretroviral therapies at conception, 0.04% for those specifically taking efavirenz at conception, and 0.08% in HIV-uninfected mothers, according to the report, which was simultaneously published in the New England Journal of Medicine.

“While there may be a risk for neural tube defects, this risk is small, and really importantly, needs to be weighed against the large potential benefits of dolutegravir,” investigator Rebecca M. Zash, MD, of Beth Israel Deaconess Medical Center, Boston, said here in Mexico City during an IAS 2019 video press conference.

The WHO had previously sounded a note of caution, saying that DTG could be “considered” in women of childbearing age if other first‐line antiretroviral agents such as efavirenz could not be used.

However, following release of new evidence, including the study by Dr. Zash and colleagues, the WHO has come out with a clear recommendation for HIV drug as “the preferred first-line and second-line treatment for all populations, including pregnant women and those of childbearing potential.”

The updated scientific reports and guidelines have important implications for global health. “Many countries have been working to make dolutegravir-based treatment their preferred first-line regimen, as it’s got several advantages over efavirenz, which people have been using for many years now, including its tolerability and resistance profiles, and its impact on morbidity and mortality,” IAS president Anton Pozniak, MD, said in the press conference.

Some countries paused their plans to roll out dolutegravir-based regimens after the preliminary safety signal from the Tsepamo study was reported, Dr. Pozniak added.

In another study presented at IAS looking at dolutegravir use at conception, investigators described an additional surveillance study in Botswana, conducted independently from the Tsepamo study. One neural tube defect was found among 152 deliveries in mothers who had been taking DTG at conception (0.66%), and two neural tube defects among 2,326 deliveries to HIV-negative mothers (0.09%).

Although the number of deliveries are small in this study, the results suggest a risk of neural tube defects with DTG exposure at conception of less than 1%, said Mmakgomo Mimi Raesima, MD, MPH, public health specialist, Ministry of Health and Wellness, Botswana.

Because neural-tube defects might be related to low folate levels, Dr. Raesima said “conversations are continuing” with regard to folate food fortification in Botswana, a country that does not mandate folate-fortified grains.

“We want to capitalize on the momentum from these results,” Dr. Raesima said in the press conference.

The Tsepamo study was funded by the National Institutes of Health. Dr. Zash reported grants during the conduct of the study from the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

SOURCE: Zash R et al. N Engl J Med. 2019 Jul 22. doi: 10.1056/NEJMoa1905230.

The risk of neural tube defects linked to dolutegravir exposure during pregnancy is lower than previously signaled, according to new reports that have prompted the World Health Organization (WHO) to confirm that this antiviral medication should be the preferred option across all populations.

alexskopje/Thinkstock

The use of dolutegravir (DTG) during pregnancy has been a pressing global health question since May 2018, when an unplanned interim analysis of the Tsepamo surveillance study of birth outcomes in Botswana showed four neural tube defects associated with dolutegravir exposure among 426 infants born to HIV-positive women (0.94%).

With follow-up for additional births, however, just one more neural tube defect was identified out of 1,683 deliveries among women who had taken DTG around the time of conception (0.30%), according to a report just presented here at the at the International AIDS Society Conference on HIV Science.

By comparison, prevalence rates of neural tube defects were 0.10% for mothers taking other antiretroviral therapies at conception, 0.04% for those specifically taking efavirenz at conception, and 0.08% in HIV-uninfected mothers, according to the report, which was simultaneously published in the New England Journal of Medicine.

“While there may be a risk for neural tube defects, this risk is small, and really importantly, needs to be weighed against the large potential benefits of dolutegravir,” investigator Rebecca M. Zash, MD, of Beth Israel Deaconess Medical Center, Boston, said here in Mexico City during an IAS 2019 video press conference.

The WHO had previously sounded a note of caution, saying that DTG could be “considered” in women of childbearing age if other first‐line antiretroviral agents such as efavirenz could not be used.

However, following release of new evidence, including the study by Dr. Zash and colleagues, the WHO has come out with a clear recommendation for HIV drug as “the preferred first-line and second-line treatment for all populations, including pregnant women and those of childbearing potential.”

The updated scientific reports and guidelines have important implications for global health. “Many countries have been working to make dolutegravir-based treatment their preferred first-line regimen, as it’s got several advantages over efavirenz, which people have been using for many years now, including its tolerability and resistance profiles, and its impact on morbidity and mortality,” IAS president Anton Pozniak, MD, said in the press conference.

Some countries paused their plans to roll out dolutegravir-based regimens after the preliminary safety signal from the Tsepamo study was reported, Dr. Pozniak added.

In another study presented at IAS looking at dolutegravir use at conception, investigators described an additional surveillance study in Botswana, conducted independently from the Tsepamo study. One neural tube defect was found among 152 deliveries in mothers who had been taking DTG at conception (0.66%), and two neural tube defects among 2,326 deliveries to HIV-negative mothers (0.09%).

Although the number of deliveries are small in this study, the results suggest a risk of neural tube defects with DTG exposure at conception of less than 1%, said Mmakgomo Mimi Raesima, MD, MPH, public health specialist, Ministry of Health and Wellness, Botswana.

Because neural-tube defects might be related to low folate levels, Dr. Raesima said “conversations are continuing” with regard to folate food fortification in Botswana, a country that does not mandate folate-fortified grains.

“We want to capitalize on the momentum from these results,” Dr. Raesima said in the press conference.

The Tsepamo study was funded by the National Institutes of Health. Dr. Zash reported grants during the conduct of the study from the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

SOURCE: Zash R et al. N Engl J Med. 2019 Jul 22. doi: 10.1056/NEJMoa1905230.