Tenofovir Alafenamide Fumarate

▎药明康德内容团队编辑 得益于有效的抗逆转录病毒疗法（ART），许多艾滋病毒（HIV）感染者可达到正常或接近正常的预期寿命。近年来，随着初始治疗方式的增加、转换治疗新方法的出现以及合并感染的有效管理，临床对于HIV感染的管理也在不断完善。 近期，国际抗病毒协会-美国分会（IAS-USA）根据最新临床循证医学证据进展，更新了《IAS-USA共识：抗逆转录病毒药物用于预防和治疗成人艾滋病毒感染（2024年）》，为临床艾滋病的预防、治疗、临床管理提供了最新专家建议。此外，该共识针对HIV实验室检测、高危风险人群的治疗，以及HIV预防提出了相关推荐建议，再次强调HIV感染者快速抑制病毒对个体健康的好处（检测不到=不会传播）。该共识发表于《美国医学会杂志》（JAMA）。《医学新视点》为您整理该共识核心内容，以飨读者。 截图来源：JAMA 所有HIV感染者均需要接受抗逆转录病毒疗法 所有HIV感染者均应接受抗逆转录病毒治疗，具体启动治疗推荐如下： 建议在确诊后尽快接受抗逆转录病毒治疗，理想情况下7天内应接受治疗，若个体已准备好就诊且未怀疑其合并有机会性感染的可能，则这7天包含了确诊当天或首次门诊就诊的时间（证据等级：AⅢ）； 应采用循证医学策略来解决以下问题：抗逆转录病毒治疗延迟（包含当天），存在影响或持续影响患者接受接受抗逆转录病毒治疗的情况，以及患者存在治疗依从性障碍的问题（证据等级：AⅡa）； 建议急性HIV感染或孕期女性接受抗逆转录病毒治疗（证据等级：AⅡa）； 对于大多数机会性感染患者，建议启动治疗2周内就进行抗逆转录病毒治疗： ——对于并无结核性脑膜炎证据的活动性肺结核患者，应在开始结核治疗后2周内开始抗逆转录病毒治疗，特别是CD4+细胞计数低于50个/μL的患者（证据等级：AⅠa）； ——对于结核性脑膜炎患者，应在确诊时立即开始大剂量皮质类固醇和结核病治疗，并在结核性脑膜炎得到控制时，根据患者临床改善和脑脊液参数情况，在2~4周内开始抗逆转录病毒治疗（证据等级：BⅠa）； ——对于隐球菌性脑膜炎患者，若存在可密切监测和治疗的颅内压升高和免疫重建炎症综合征（IRIS，艾滋病患者在抗逆转录病毒治疗后免疫恢复过程中出现的一组临床综合征），建议在开始抗真菌治疗后2~4周开始抗逆转录病毒治疗；若患者临床症状改善、颅内压得到控制、抗真菌治疗后脑脊液培养阴性，可继续密切监测的患者，建议在抗真菌治疗后2周开始抗逆转录病毒治疗；若未达到上述标准，则在抗真菌治疗4周后，开始抗逆转录病毒治疗（证据等级：BⅢ）； ——对于无症状的隐球菌抗原血症且腰椎穿刺阴性的抗逆转录病毒初始治疗患者，建议立即开始抗逆转录病毒治疗，优先考虑使用氟康唑（证据等级：BⅢ）； 对于新确诊癌症的HIV感染者，应立即开始抗逆转录病毒治疗，并注意用药时的药物相互作用影响（证据等级：AⅡa）； 初始抗逆转录病毒疗法方案的选择 在推荐的初始抗逆转录病毒治疗方案方面，本次共识建议与前一版本相同，大体如下： 对于大多数HIV感染者，初始治疗多推荐比克替拉韦（bictegravir）、多替拉韦（DTG）、整合酶抑制剂（InSTIs）的组合治疗方案，因为该方案具有高病毒抑制率、良好耐受性、罕见毒副作用、有限的药物相互作用、高耐药屏障和低药物负担（证据等级：AⅠa）； 初始抗病毒治疗方案中核苷类或核苷类反转录酶抑制剂（NRTI）重要构成，包括丙酚替诺福韦（TAF）或替诺福韦（TDF），以及恩曲他滨（FTC）或拉米夫定（3TC）（证据等级：AⅠa）； 初始抗病毒治疗复方单片制剂推荐多替拉韦或拉米夫定（DTG/3TC）（证据等级：AⅠa）。但如果检测到患者拉米夫定耐药，或HIV RNA水平≥500000 copies/ml，或合并乙肝病毒感染，则不建议使用DTG/3TC（证据等级：AⅠa），因此，如果没有上述相关检查结果，则不建议使用DTG/3TC作为初始治疗方案。此外，由于妊娠期使用DTG/3TC的临床数据有限，不建议在此期间使用；类似地，对于CD4+细胞计数＜200个/μL的个体，初始治疗使用DTG/3TC的数据也比较有限。 在耐药检测结果出来之前，若怀疑患者整合酶抑制剂耐药，则建议使用含达芦那韦（DRV）加强方案，特别是既往接受长效卡替拉韦（CAB-LA）作为暴露前预防（PrEP）的个体（证据等级：AⅡb）。若排除耐药性，则可替换为整合酶抑制剂或非核苷类反转录酶抑制剂为基础的治疗策略。 对于使用丙酚替诺福韦或替诺福韦/恩曲他滨或拉米夫定作为暴露前预防期间感染HIV-1的感染者，在获得耐药性结果之前，可考虑使用比克替拉韦联合丙酚替诺福韦或替诺福韦/恩曲他滨或拉米夫定。但耐药结果出来后，应根据实际情况告知患者应使用哪种治疗方案。 图片来源：123RF 体重增加和合并心脏代谢风险的HIV感染者治疗 不同抗逆转录病毒药物带来的体重变化存在差异，大部分情况下，接受抗逆转录病毒治疗的患者体重变化＜5%，也有少部分患者体重会增加10%。目前，临床正在探索关于用药后体重增加的预测和决定因素，以及用药后体重增加能否逆转（临床实际较少观察到患者体重恢复至用药前）。共识相关建议如下： 对于开始或转换使用整合酶抑制剂或丙酚替诺福韦方案的个体，建议在基线时，以及每6个月测量和记录一次体重和体重指数，以识别体重过度增加的个体（证据等级：AⅡa）； 建议在每次临床访视时测量血压，以及时诊断和治疗高血压（证据等级：AⅢ）； 不建议因体重增加（证据等级：BⅠa）、高血压（证据等级：BⅢ）或胰岛素抵抗（证据等级：BⅢ）而更改治疗方案； 对于高风险或患有心血管疾病且正在接受阿巴卡韦的患者，如有其他可用有效方案，应改用不含阿巴卡韦的治疗方案（证据等级：AⅡb）； 对于开始抗逆转录病毒治疗的患者，特别是接受整合酶抑制剂、丙酚替诺福韦方案后体重增加（证据等级：AⅢ），以及由于高血压、胰岛素抵抗/糖尿病、吸烟、其他因素导致心血管疾病风险增加（证据等级：AⅢ），建议进行相关潜在心脏代谢并发症和改变生活方式（运动和饮食）的咨询。 10年心血管疾病风险≥20%或低密度脂蛋白胆固醇水平≥4.92 mmol/L（190 mg/dl）的HIV感染者，应接受高强度他汀治疗；糖尿病患者应至少接受中等强度他汀治疗（证据等级：AⅠa）； 年龄40~75岁，10年心血管疾病风险5%~20%（低或中等风险）的HIV感染者，应接受至少一种中等强度他汀治疗，如4 mg匹伐他汀（证据等级：AⅠa）、20 mg阿托伐他汀（证据等级：AⅡa）、10 mg瑞舒伐他汀（证据等级：AⅡa）。 对于10年心血管疾病风险＜5%的HIV感染者，仍建议使用中等强度他汀治疗（证据等级：CⅠa），支持这一建议主要是考虑到存在心血管疾病风险增加因素、HIV风险增强因素（延迟抗逆转录病毒治疗启动史、当前/最低CD4+细胞计数＜350个/μL、HIV治疗失败、代谢综合征、脂肪代谢障碍、脂肪肝相关疾病、合并丙肝感染）。 抗逆转录病毒疗法和预防HIV感染的未来趋势 新的长效抗逆转录病毒疗法即将问世。2024年10月时，仅有一种长效注射抗逆转录病毒疗法（长效卡替拉韦联合长效利匹韦林）获批上市，用法为每月一次或每两月一次。其他临床方案也正在研发中，如每周一次的islatravir联合lenacapavir。一项2期随访研究发现，每周接受较低剂量（2 mg）的islatravir治疗，第48周时可达到与比克替拉韦/丙酚替诺福韦/恩曲他滨相当的病毒高抑制率，且不影响淋巴细胞计数水平。 目前，已开展几项关于广谱中和抗体（bNAb）应用于HIV感染者，以维持HIV RNA抑制的探索性研究，如2种广谱中和抗体与lenacapavir联用，以及单种广谱中和抗体与卡替拉韦联用。简化抗逆转录病毒疗法是过去十多年来一贯的目标，每日一片的lenacapavir/比克替拉韦临床3期研究正在进行中。 MK-8527是一种核苷类反转录酶易位抑制剂，目前正在进行每月口服一次剂量的相关2期临床试验。静脉注射和皮下批注长效广谱中和抗体组合（被动免疫）正在研发中，用于预防HIV感染。一种间隔4个月肌内注射的长效卡替拉韦也正在开展相关临床试验。 小结 随着HIV感染疗法的不断改进，临床提出了更多方案，如耐受性良好和高效的口服方案，以及针对那些不愿意接受治疗或难以坚持日常治疗的人提供的长效注射方案。此外，针对HIV感染者维持健康的新策略也在更新，如扩大他汀类药物的适应证，以减少心血管事件的发生等。每日口服暴露前预防口服药物或长效注射剂，是预防和早日终结艾滋病的关键。 附：该共识相关推荐建议强度和证据等级说明 点击文末“阅读原文/Read more”，即可访问JAMA官网阅读完整论文。 推荐阅读 欢迎投稿：学术成果、前沿进展、临床干货等主题均可，点此了解投稿详情。 参考资料 [1] Gandhi RT, Landovitz RJ, Sax PE, et al. Antiretroviral Drugs for Treatment and Prevention of HIV in Adults: 2024 Recommendations of the International Antiviral Society–USA Panel. JAMA. Published online December 01, 2024. doi:10.1001/jama.2024.24543 免责声明：药明康德内容团队专注介绍全球生物医药健康研究进展。本文仅作信息交流之目的，文中观点不代表药明康德立场，亦不代表药明康德支持或反对文中观点。本文也不是治疗方案推荐。如需获得治疗方案指导，请前往正规医院就诊。 版权说明：本文来自药明康德内容团队，欢迎个人转发至朋友圈，谢绝媒体或机构未经授权以任何形式转载至其他平台。转载授权请在「医学新视点」微信公众号留言联系。 如有其他合作需求，请联系wuxi_media@wuxiapptec.com 分享，点赞，在看，传递医学新知

RAHWAY, N.J.--( BUSINESS WIRE )--Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced topline results from two pivotal Phase 3 trials of the investigational, once-daily, oral, two-drug, single-tablet regimen of doravirine/islatravir [DOR/ISL (100 mg/0.25 mg)] in adults with HIV-1 infection that is virologically suppressed on different antiretroviral therapy regimens [baseline antiretroviral therapy (bART)]; MK-8591A-051 or bictegravir/emtricitabine/tenofovir alafenamide i [BIC/FTC/TAF (50 mg/200 mg/25 mg)]; MK-8591A-052 . The success criterion for the primary efficacy hypothesis, as measured by the percentage of participants with HIV-1 RNA levels ≥50 copies/mL at Week 48, was met in both trials. DOR/ISL was demonstrated to be non-inferior to bART in open-label trial MK-8591A-051 and non-inferior to BIC/FTC/TAF in double-blind trial MK-8591A-052. The superiority criteria were not met in trial MK-8591A-052. Primary safety objectives of both trials were also met. The company is planning to present detailed findings from these trials at a future scientific congress and will also plan to file these data with regulatory authorities. In the U.S., doravirine is approved for the treatment of adults with HIV-1 in combination with other antiretrovirals, as a single agent (PIFELTRO) and a component of a single-tablet regimen [DELSTRIGO; doravirine, lamivudine, and tenofovir disoproxil fumarate (DOR/3TC/TDF)]. “ We are encouraged by the results from these Phase 3 trials evaluating a once-daily, oral, two-drug, single-tablet regimen of doravirine and islatravir,” said Dr. Eliav Barr, senior vice president, head of global clinical development and chief medical officer, Merck Research Laboratories. “ We are committed to advancing our clinical programs for islatravir in combination with other antiretrovirals as potential options to help address the needs of people living with HIV.” Islatravir (MK-8591), Merck’s investigational nucleoside reverse transcriptase translocation inhibitor (NRTTI), exhibits both transcriptase and translocation inhibition (which prevents nucleotide binding and incorporation to the DNA chain, resulting in immediate chain termination) and delayed chain termination (which prevents nucleotide incorporation even in the event of translocation). Islatravir is being evaluated in multiple early and late-stage clinical trials in combination with other antiretroviral therapies for the treatment of HIV-1. In addition to the MK-8591A-051 and MK-8591A-052 trials, ongoing Phase 3 trials of DOR/ISL include MK-8591A-053 in people with HIV who had not previously received treatment (treatment-naïve), and MK-8591A-054 evaluating open-label DOR/ISL (100 mg/0.25 mg) in individuals who participated in earlier Phase 3 trials of DOR/ISL (100 mg/0.75 mg). About MK-8591A-051 ( NCT05631093 ) MK-8591A-051 is a Phase 3, randomized, active-controlled, open-label clinical trial evaluating a switch to investigational, oral, once-daily DOR/ISL (100 mg/0.25 mg) in adults with HIV-1 infection that has been virologically suppressed using ART. Participants (n=551) were randomized 2:1 to either switch to investigational DOR/ISL or continue with their current bART regimen through Week 48. After Week 48, all participants receive DOR/ISL through Week 144 of the trial. After Week 144, eligible participants may continue on DOR/ISL and continue trial treatment until Week 240 or when DOR/ISL becomes commercially accessible (whichever comes first). The primary efficacy (percentage of participants with HIV-1 RNA levels ≥50 copies/mL) and safety (number of participants experiencing adverse events (AEs) and discontinuing trial intervention due to AEs) endpoints were assessed at Week 48. About MK-8591A-052 ( NCT05630755 ) MK-8591A-052 is a Phase 3, randomized, active-controlled, double-blind clinical trial evaluating a switch to investigational, oral, once-daily DOR/ISL (100mg /0.25mg) in adults with HIV-1 infection that has been virologically suppressed using BIC/FTC/TAF (50 mg/200 mg/25 mg). Participants (n=513) were randomized 2:1 to either switch to DOR/ISL or continue on BIC/FTC/TAF through Week 144. After Week 144, eligible participants may continue on DOR/ISL and continue trial treatment until Week 240 or when DOR/ISL becomes commercially accessible (whichever comes first). The primary efficacy (percentage of participants with HIV-1 RNA levels ≥50 copies/mL) and safety (number of participants experiencing AEs and discontinuing trial intervention due to AEs) endpoints were assessed at Week 48. Indications and usage for PIFELTRO and DELSTRIGO in the U.S. PIFELTRO is indicated in combination with other antiretroviral (ARV) agents for the treatment of HIV-1 infection in adult patients with no prior ARV treatment history or to replace the current ARV regimen in those who are virologically suppressed (HIV-1 RNA less than 50 copies per mL) on a stable ARV regimen with no history of treatment failure and no known substitutions associated with resistance to doravirine. DELSTRIGO is indicated as a complete regimen for the treatment of HIV-1 infection in adult patients with no prior ARV treatment history or to replace the current ARV regimen in those who are virologically suppressed (HIV-1 RNA less than 50 copies per mL) on a stable ARV regimen with no history of treatment failure and no known substitutions associated with resistance to the individual components of DELSTRIGO. Selected Safety Information Warning: Posttreatment Acute Exacerbation of Hepatitis B (HBV) All patients with HIV-1 should be tested for the presence of HBV before initiating ARV therapy. Severe acute exacerbations of HBV have been reported in people with concomitant HIV-1 and HBV who have discontinued products containing lamivudine or tenofovir disoproxil fumarate (TDF), which are components of DELSTRIGO. Patients coinfected with HIV-1 and HBV who discontinue DELSTRIGO should be monitored with both clinical and laboratory follow-up for at least several months after stopping DELSTRIGO. If appropriate, initiation of anti-HBV therapy may be warranted. Contraindications PIFELTRO and DELSTRIGO are contraindicated when coadministered with drugs that are strong cytochrome P450 (CYP)3A enzyme inducers (including the anticonvulsants carbamazepine, oxcarbazepine, phenobarbital, and phenytoin; the androgen receptor inhibitor enzalutamide; the antimycobacterials rifampin and rifapentine; the cytotoxic agent mitotane; and the herbal product St. John’s wort (Hypericum perforatum)), as significant decreases in doravirine plasma concentrations may occur, which may decrease the effectiveness of DELSTRIGO and PIFELTRO. DELSTRIGO is contraindicated in patients with a previous hypersensitivity reaction to lamivudine. Warnings and Precautions Severe Skin Reactions Severe skin reactions, including Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), have been reported during the postmarketing experience with doravirine-containing regimens. Discontinue PIFELTRO or DELSTRIGO, and other medications known to be associated with severe skin reactions, immediately if a painful rash with mucosal involvement or a progressive severe rash develops. Clinical status should be closely monitored, and appropriate therapy should be initiated. New or Worsening Renal Impairment Renal impairment, including cases of acute renal failure and Fanconi syndrome, have been reported with the use of TDF. DELSTRIGO should be avoided with concurrent or recent use of a nephrotoxic agent (eg, high-dose or multiple NSAIDs). Cases of acute renal failure after initiation of high-dose or multiple NSAIDs have been reported in people living with HIV with risk factors for renal dysfunction who appeared stable on TDF. Prior to or when initiating DELSTRIGO, and during treatment, assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein in all patients. In patients with chronic kidney disease, also assess serum phosphorus. Discontinue DELSTRIGO in patients who develop clinically significant decreases in renal function or evidence of Fanconi syndrome. Discontinue DELSTRIGO if estimated creatinine clearance declines below 50 mL/min. Bone Loss and Mineralization Defects In clinical trials in adults living with HIV, TDF was associated with slightly greater decreases in bone mineral density (BMD) and increases in biochemical markers of bone metabolism. Serum parathyroid hormone levels and 1,25 Vitamin D levels were also higher. Cases of osteomalacia associated with proximal renal tubulopathy have been reported with the use of TDF. Immune Reconstitution Syndrome Immune reconstitution syndrome can occur, including the occurrence of autoimmune disorders with variable time to onset, which may necessitate further evaluation and treatment. Drug Interactions Because DELSTRIGO is a complete regimen, coadministration with other antiretroviral medications for the treatment of HIV-1 infection is not recommended. Coadministration of PIFELTRO with efavirenz, etravirine, or nevirapine is not recommended. If DELSTRIGO is coadministered with rifabutin, take one tablet of DELSTRIGO once daily, followed by one tablet of doravirine (PIFELTRO) approximately 12 hours after the dose of DELSTRIGO. If PIFELTRO is coadministered with rifabutin, increase PIFELTRO dosage to one tablet twice daily (approximately 12 hours apart). Consult the full Prescribing Information prior to and during treatment for more information on potential drug-drug interactions. Dosage and Administration/Specific Populations Renal Impairment Because DELSTRIGO is a fixed-dose combination tablet and the dosage of lamivudine and TDF cannot be adjusted, DELSTRIGO is not recommended in patients with estimated creatinine clearance less than 50 mL/min. Adverse Reactions The most common adverse reactions with DELSTRIGO (incidence ≥5%, all intensities) were dizziness (7%), nausea (5%), and abnormal dreams (5%). The most common adverse reactions with PIFELTRO (incidence ≥5%, all intensities) were nausea (7%), dizziness (7%), headache (6%), fatigue (6%), diarrhea (6%), abdominal pain (5%), and abnormal dreams (5%). By week 96 in DRIVE-FORWARD, 2% of adult participants in the PIFELTRO group and 3% in the darunavir+ritonavir (DRV+r) group had adverse events leading to discontinuation of study medication. By week 96 in DRIVE-AHEAD, 3% of adult participants in the DELSTRIGO group and 7% in the efavirenz (EFV)/emtricitabine (FTC)/TDF group had adverse events leading to discontinuation of study medication. In DRIVE-FORWARD, mean changes from baseline at week 48 in LDL-cholesterol (LDL-C) and non-HDL-cholesterol (non-HDL-C) were pre-specified. LDL-C: -4.6 mg/dL in the PIFELTRO group vs 9.5 mg/dL in the DRV+r group. Non-HDL-C: -5.4 mg/dL in the PIFELTRO group vs 13.7 mg/dL in the DRV+r group. The clinical benefits of these findings have not been demonstrated. In DRIVE-AHEAD, mean changes from baseline at week 48 in LDL-C and non-HDL-C were pre-specified. LDL-C: -2.1 mg/dL in the DELSTRIGO group vs 8.3 mg/dL in the EFV/FTC/TDF group. Non-HDL-C: -4.1 mg/dL in the DELSTRIGO group vs 12.7 mg/dL in the EFV/FTC/TDF group. The clinical benefits of these findings have not been demonstrated. In DRIVE-SHIFT, mean changes from baseline at week 24 in LDL-C and non-HDL-C were pre-specified. LDL-C: -16.3 mg/dL in the DELSTRIGO group vs -2.6 mg/dL in the PI + ritonavir group. Non-HDL-C: -24.8 mg/dL in the DELSTRIGO group vs -2.1 mg/dL in the PI + ritonavir group. The clinical benefits of these findings have not been demonstrated. In DRIVE-AHEAD, neuropsychiatric adverse events were reported in the three pre-specified categories of sleep disorders and disturbances, dizziness, and altered sensorium. Twelve percent of adult participants in the DELSTRIGO group and 26% in the EFV/FTC/TDF group reported neuropsychiatric adverse events of sleep disorders and disturbances; 9% in the DELSTRIGO group and 37% in the EFV/FTC/TDF group reported dizziness; and 4% in the DELSTRIGO group and 8% in the EFV/FTC/TDF group reported altered sensorium. The safety of DELSTRIGO in virologically-suppressed adults was based on week 48 data from participants in the DRIVE-SHIFT trial. Overall, the safety profile in virologically-suppressed adult participants was similar to that in participants with no ARV treatment history. Serum ALT and AST Elevations: In the DRIVE-SHIFT trial, 22% and 16% of participants in the immediate switch group experienced ALT and AST elevations greater than 1.25 X ULN, respectively, through 48 weeks on DELSTRIGO. For these ALT and AST elevations, no apparent patterns with regard to time to onset relative to switch were observed. One percent of participants had ALT or AST elevations greater than 5 X ULN through 48 weeks on DELSTRIGO. The ALT and AST elevations were generally asymptomatic, and not associated with bilirubin elevations. In comparison, 4% and 4% of participants in the delayed switch group experienced ALT and AST elevations of greater than 1.25 X ULN through 24 weeks on their baseline regimen. Pregnancy/Breastfeeding There is a pregnancy exposure registry that monitors pregnancy outcomes in individuals exposed to PIFELTRO or DELSTRIGO during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Inform individuals with HIV-1 infection of the potential risks of breastfeeding, including: (1) HIV-1 transmission (in HIV-1–negative infants), (2) developing viral resistance (in HIV-1–positive infants), and (3) serious adverse reactions in a breastfed infant similar to those seen in adults. About Islatravir (MK-8591) and Merck’s HIV Research Islatravir (MK-8591) is Merck’s investigational nucleoside reverse transcriptase translocation inhibitor (NRTTI) under evaluation in multiple ongoing early and late-stage clinical studies in combination with other antiretrovirals for the treatment of HIV-1. Studies with islatravir are designed to offer different dosing options as potential daily and once-weekly treatments. For an overview of Merck’s HIV treatment and prevention clinical development program, please click here . Merck’s Commitment to HIV For more than 35 years, Merck has been committed to scientific research and discovery in HIV leading to scientific breakthroughs that have helped change HIV treatment. Our work has been pioneering in the development of new options across multiple drug classes to help those impacted by HIV. Today, we are developing a series of antiviral options designed to help people manage HIV and protect people from HIV, with the goal of reducing the growing burden of infection worldwide. We want to ensure people are not defined by HIV and our work focuses on transformational innovations, collaborations with others in the global HIV community, and access initiatives aimed at the goal of helping to end the HIV epidemic for everyone. About Merck At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit www.merck.com and connect with us on X (formerly Twitter) , Facebook , Instagram , YouTube and LinkedIn . Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA This news release of Merck & Co., Inc., Rahway, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements. Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions. The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s Annual Report on Form 10-K for the year ended December 31, 2023, and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site ( www.sec.gov ). Please see Prescribing Information for PIFELTRO (doravirine) at: https://www.merck.com/product/usa/pi_circulars/p/pifeltro/pifeltro_pi.pdf and Patient Information for PIFELTRO (doravirine) at: https://www.merck.com/product/usa/pi_circulars/p/pifeltro/pifeltro_ppi.pdf Please see Prescribing Information for DELSTRIGO (doravirine, lamivudine, and tenofovir disoproxil fumarate) at: https://www.merck.com/product/usa/pi_circulars/d/delstrigo/delstrigo_pi.pdf and Patient Information for DELSTRIGO (doravirine, lamivudine, and tenofovir disoproxil fumarate) https://www.merck.com/product/usa/pi_circulars/d/delstrigo/delstrigo_ppi.pdf i bictegravir/emtricitabine/tenofovir alafenamide (BIKTARVY) is a registered trademark of Gilead Sciences, Inc.