Mitotane

The Cushing's disease pipeline possesses some drugs in mid and late-stage development to be approved in the near future. The emerging landscape holds a diverse range of therapeutic alternatives for treatment, including relacorilant, clofutriben, atumelnant, and others. The expected launch of these therapies shall further create a positive impact on the Cushing's disease market. LAS VEGAS, May 15, 2025 /PRNewswire/ -- DelveInsight's Cushing's Disease Market Insights report includes a comprehensive understanding of current treatment practices, Cushing's disease emerging drugs, market share of individual therapies, and current and forecasted market size from 2020 to 2034, segmented into 7MM [the United States, the EU4 (Germany, France, Italy, and Spain) and the United Kingdom, and Japan]. Key Takeaways from the Cushing's Disease Market Report According to DelveInsight's analysis, the market size for Cushing's disease was found to be USD 1 billion in the 7MM in 2024. In 2024, among all the current therapies for Cushing's disease, the highest revenue was generated by Mifepristone (KORLYM and generics) in the US. Based on DelveInsight's assessment in 2024, the 7MM had approximately 37K diagnosed prevalent cases of Cushing's disease. These cases are expected to rise due to advancements in diagnostic capabilities and increased awareness about the disease during the forecast period (2025–2034). Leading Cushing's disease companies developing emerging therapies, such as Corcept Therapeutics, Sparrow Pharmaceuticals, Crinetics Pharmaceuticals, H. Lundbeck, Stero Therapeutics, and others, are developing novel Cushing's disease drugs that can be available in the Cushing's disease market in the coming years. The promising Cushing's disease therapies in the pipeline include DUPIXENT (dupilumab), Linerixibat (GSK2330672), NEMLUVIO/MITCHGA (nemolizumab), Volixibat, and others. In March 2025, Corcept Therapeutics announced that the FDA had assigned a PDUFA target action date of December 30, 2025, for relacorilant to treat patients with endogenous hypercortisolism. In February 2025, Crinetics Pharmaceuticals mentioned that the company anticipates beginning enrollment for Atumelnant (CRN04894) in Phase Ib/IIa trials for Cushing's disease in late 2025 or early 2026. In October 2024, Sparrow Pharmaceuticals announced that clofutriben had been granted Orphan Drug Designation (ODD) by the US FDA for the treatment of endogenous Cushing's syndrome. Discover which therapies are expected to grab the major Cushing's disease market share @ Cushing's Disease Market Report Cushing's Disease Overview Cushing's disease is a rare but serious endocrine disorder caused by a pituitary tumor that triggers excessive cortisol production. It presents with a variety of symptoms such as weight gain, fatigue, mood disturbances, high blood pressure, and impaired glucose tolerance. Cushing's syndrome is responsible for 80–85% of hypercortisolism cases, with 75–80% of those linked to ACTH-producing pituitary adenomas. Without treatment, the 5-year survival rate is only about 50%, emphasizing the urgent need for effective therapies. Diagnosing Cushing's disease is especially difficult because it is rare, shares symptoms with other disorders, and presents in various ways. Only 40–60% of patients have a detectable tumor on standard Magnetic Resonance Imaging (MRI), and the diagnosis is often delayed by an average of 7 years. Cushing's Disease Epidemiology Segmentation The Cushing's disease epidemiology section provides insights into the historical and current Cushing's disease patient pool and forecasted trends for the 7MM. It helps recognize the causes of current and forecasted patient trends by exploring numerous studies and views of key opinion leaders. The Cushing's disease market report proffers epidemiological analysis for the study period 2020–2034 in the 7MM segmented into: Total Prevalent Cases of Cushing's Disease Total Diagnosed Prevalent Cases of Cushing's Disease Gender-Specific Diagnosed Prevalent Cases of Cushing's Disease Age-Specific Diagnosed Prevalent Cases of Cushing's Disease Cushing's Disease Treatment Market The primary treatment for Cushing's disease is usually transsphenoidal surgery to remove the pituitary tumor, which often leads to remission. However, some patients may experience a recurrence. When surgery is unsuccessful or not an option, medical therapies are used to control cortisol levels. Various medications are available for managing Cushing's disease, especially in cases where surgery is ineffective or not feasible. One such drug is KORLYM, developed by Corcept Therapeutics, approved for treating hyperglycemia in patients with Cushing's syndrome who also have Type 2 diabetes or glucose intolerance. In 2024, a generic version by Teva Pharmaceuticals entered the market, adding competition, and Corcept itself has released a generic version as well. Other approved options include S IGNIFOR and SIGNIFOR LAR, ISTURISA, and RECORLEV. In addition, off-label drugs like ketoconazole, metyrapone, cabergoline, mitotane, and etomidate are also used in the U.S., with some marketed in Europe by HRA Pharma. SIGNIFOR (pasireotide), developed by Recordati, was the first drug specifically approved for Cushing's disease by the FDA in 2012, and also gained EU approval. Recordati also markets SIGNIFOR LAR, a long-acting injectable version approved by the FDA and Japan's PMDA in 2018. This formulation, administered intramuscularly once every four weeks, shares the same mechanism as SIGNIFOR but offers a different delivery route. Recordati is recognized as a leading player in this therapeutic area. Another key product from the company is ISTURISA (osilodrostat), the first FDA-approved oral drug that inhibits cortisol production by targeting the enzyme 11β-hydroxylase (CYP11B1), which is involved in the final step of cortisol synthesis. Its oral administration makes it more convenient for patients compared to injectable therapies. ISTURISA is also being studied for pediatric use in an ongoing Phase II trial (NCT03708900). RECORLEV, originally developed by Strongbridge Biopharma and later acquired by Xeris Pharmaceuticals, was approved by the FDA in 2021. It is indicated for adults with endogenous Cushing's syndrome who are not surgical candidates or did not achieve a cure through surgery. Unlike ISTURISA, RECORLEV works by inhibiting cortisol production at multiple points in the steroidogenesis pathway, offering a distinct mechanism of action. To know more about Cushing's disease treatment guidelines, visit @ Cushing's Disease Management Cushing's Disease Pipeline Therapies and Key Companies Relacorilant (CORT125134): Corcept Therapeutics Clofutriben (SPI-62): Sparrow Pharmaceuticals Atumelnant (CRN04894): Crinetics Pharmaceuticals Lu AG13909: H. Lundbeck ST-002: Stero Therapeutics Discover more about Cushing's disease drugs in development @ Cushing's Disease Clinical Trials Cushing's Disease Market Dynamics The Cushing's disease market dynamics are expected to change in the coming years. Although Cushing's disease is generally considered a rare condition, growing awareness and recent advances in research suggest that diagnoses may rise in the future; despite a seemingly crowded market, many current hypercortisolism treatments fail to normalize cortisol levels effectively and pose significant side effects highlighting a substantial opportunity for innovation, especially given the limited therapies specifically targeting Cushing's disease and the potential of newer oral alternatives like ISTURISA and RECORLEV to offer greater flexibility compared to SC and intramuscular options such as SIGNIFOR and SIGNIFOR LAR. Furthermore, potential therapies are being investigated for the treatment of Cushing's disease, and it is safe to predict that the treatment space will significantly impact the Cushing's disease market during the forecast period. Moreover, the anticipated introduction of emerging therapies with improved efficacy and a further improvement in the diagnosis rate are expected to drive the growth of the Cushing's disease market in the 7MM. However, several factors may impede the growth of the Cushing's disease market. Due to non-specific guidelines and recommendations, patients with Cushing's disease often face suboptimal care, delayed diagnosis, and inconsistent treatment approaches, further compounded by the diagnostic complexity, frequent misdiagnosis, and symptom overlap with more common conditions, which leave many undiagnosed or untreated; while existing therapies such as ketoconazole and metyrapone approved in Europe based on limited retrospective data and used off-label in the US despite high costs are widely trusted and entrenched in clinical practice, posing a significant barrier to the adoption of emerging therapies. Moreover, Cushing's disease treatment poses a significant economic burden and disrupts patients' overall well-being and QOL. Furthermore, the Cushing's disease market growth may be offset by failures and discontinuation of emerging therapies, unaffordable pricing, market access and reimbursement issues, and a shortage of healthcare specialists. In addition, the undiagnosed, unreported cases and the unawareness about the disease may also impact the Cushing's disease market growth. Scope of the Cushing's Disease Market Report Therapeutic Assessment: Cushing's Disease current marketed and emerging therapies Cushing's Disease Market Dynamics: Key Market Forecast Assumptions of Emerging Cushing's Disease Drugs and Market Outlook Competitive Intelligence Analysis: SWOT analysis and Market entry strategies Unmet Needs, KOL's views, Analyst's views, Cushing's Disease Market Access and Reimbursement Download the report to understand which factors are driving Cushing's disease market trends @ Cushing's Disease Market Trends Table of Contents Related Reports Cushing's Syndrome Market Cushing's Syndrome Market Insights, Epidemiology, and Market Forecast – 2034 report deliver an in-depth understanding of the disease, historical and forecasted epidemiology, as well as the market trends, market drivers, market barriers, and key Cushing's syndrome companies including Corcept Therapeutics, Crinetics Pharmaceuticals, Cyclacel Pharmaceuticals, Sparrow Pharmaceuticals, Stero Therapeutics, among others. Cushing's Syndrome Pipeline Cushing's Syndrome Pipeline Insight – 2025 report provides comprehensive insights about the pipeline landscape, pipeline drug profiles, including clinical and non-clinical stage products, and the key Cushing's syndrome companies, including Corcept Therapeutics, Crinetics Pharmaceuticals, Cyclacel Pharmaceuticals, Sparrow Pharmaceuticals, Stero Therapeutics, among others. Endogenous Cushing's Syndrome Market Endogenous Cushing's Syndrome Market Insights, Epidemiology, and Market Forecast – 2034 report deliver an in-depth understanding of the disease, historical and forecasted epidemiology, as well as the market trends, market drivers, market barriers, and key endogenous Cushing's syndrome companies including Corcept Therapeutics, Crinetics Pharmaceuticals, Sparrow Pharmaceuticals, among others. Endogenous Cushing's Syndrome Pipeline Endogenous Cushing's Syndrome Pipeline Insight – 2025 report provides comprehensive insights about the pipeline landscape, pipeline drug profiles, including clinical and non-clinical stage products, and the key endogenous Cushing's syndrome companies, including Corcept Therapeutics, Crinetics Pharmaceuticals, Sparrow Pharmaceuticals, among others. About DelveInsight DelveInsight is a leading Business Consultant and Market Research firm focused exclusively on life sciences. It supports pharma companies by providing comprehensive end-to-end solutions to improve their performance. Get hassle-free access to all the healthcare and pharma market research reports through our subscription-based platform PharmDelve . 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March 12, 2025 11:26 am ET DOR/ISL demonstrated non-inferiority and a similar safety profile to comparator antiretroviral therapies in adults with virologically suppressed HIV-1 RAHWAY, N.J.--(BUSINESS WIRE)-- Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the presentation of positive results from two pivotal Phase 3 trials of the investigational, once-daily, oral, two-drug regimen of doravirine/islatravir [DOR/ISL (100mg/0.25mg)] in adults with HIV-1 infection that is virologically suppressed on bictegravir/emtricitabine/tenofovir alafenamidei [BIC/FTC/TAF (50mg/200mg/25mg)] in trial MK-8591A-052 ) or antiretroviral therapy [baseline antiretroviral therapy (bART)] in trial MK-8591A-051. In both trials, DOR/ISL met the primary efficacy success criterion for non-inferiority to comparator antiretroviral therapies and primary safety objectives at Week 48. The findings will be shared in late-breaking oral presentations at the 32nd Conference on Retroviruses and Opportunistic Infections (CROI) being held in San Francisco and were featured in a CROI press conference. Merck plans to begin submitting applications for marketing authorization to regulatory agencies by mid-2025. In the double-blind trial MK-8591A-052 (Abstract #204A), results for the primary endpoint (HIV-1 RNA ≥50 copies/mL) showed that 1.5% of participants who switched to DOR/ISL had a viral load of ≥50 copies/mL at Week 48, compared to 0.6% on BIC/FTC/TAF (treatment difference 0.9%, 95% CI -1.9, 2.9). At Week 48, 91.5% of participants who switched to DOR/ISL maintained viral suppression (HIV-1 RNA <50 copies/mL) compared to 94.2% of participants who continued receiving BIC/FTC/TAF (treatment difference -2.6%, 95% CI -7.1, 2.6; secondary endpoint). In the open-label trial MK-8591A-051 (Abstract #204B), results for the primary endpoint (HIV-1 RNA ≥50 copies/mL) showed that 1.4% of participants who received DOR/ISL had a viral load of ≥50 copies/mL at Week 48, compared to 4.9% on bART (treatment difference -3.6%, 95% CI -7.8, -0.8. At Week 48, 95.6% of participants who switched to DOR/ISL maintained viral suppression (HIV-1 RNA <50 copies/mL) compared to 91.9% of participants who continued on bART (treatment difference 3.7%, 95% CI -0.3, 8.9; secondary endpoint). Across both trials, the safety profile of DOR/ISL was generally comparable to the comparator antiretroviral regimens, including BIC/FTC/TAF in MK-8591A-052. At Week 48, the mean percent change in total lymphocyte and CD4 counts were similar for DOR/ISL and comparator regimens. No treatment-emergent resistance to DOR or ISL was observed in either trial. “Despite the availability of multiple daily antiretroviral therapies, the needs of people living with HIV are evolving. Many people living with HIV are older and also managing comorbidities, making it important to have daily treatment options that can help meet each person’s unique health needs,” said Professor Chloe Orkin, Dean for Healthcare Transformation, Queen Mary University of London, United Kingdom. “I’m excited to see that DOR/ISL has potential as a new daily treatment option for people living with HIV who may benefit from this two-drug regimen.” Islatravir, Merck’s investigational nucleoside reverse transcriptase translocation inhibitor (NRTTI), blocks HIV-1 replication by multiple mechanisms including inhibition of reverse transcriptase translocation resulting in immediate chain termination and delayed chain termination from structural changes induced in the viral DNA. “We are excited that DOR/ISL is the first two-drug regimen without an integrase inhibitor to demonstrate comparable efficacy and safety to the three-drug InSTI-based regimen, BIC/FTC/TAF, in a Phase 3 pivotal trial,” said Dr. Eliav Barr, senior vice president, head of global clinical development and chief medical officer, Merck Research Laboratories. “Merck has been a research pioneer in HIV for decades. These data and our work on the longer-acting islatravir-based therapies in our pipeline show our continued commitment to help find new options that address the evolving needs of people living with HIV.” About the Phase 3 data from MK-8591A-052 MK-8591A-052 is a Phase 3, double-blind randomized, active-controlled, clinical trial to evaluate the efficacy and safety of a switch to investigational, oral, once-daily DOR/ISL (100mg/0.25mg) in adults with HIV-1 infection that has been virologically suppressed on BIC/FTC/TAF (50mg/200mg/25mg). The primary efficacy endpoint was the percentage of participants with HIV-1 RNA ≥50 copies/mL at Week 48 (non-inferiority margin 4%). In this trial, 513 adults with HIV-1 who had virologic suppression for three months or more on BIC/FTC/TAF, no history of treatment failure and no known resistance to DOR were randomized (2:1) and switched to DOR/ISL (n= 342) or continued treatment with BIC/FTC/TAF (n=171). The median age of participants was 47 years; 21.4% were assigned female sex at birth, 30.8% were Black or African American, and 22.8% were Hispanic or Latine. The median duration of BIC/FTC/TAF treatment prior to trial enrollment was 3.4 years (IQR 2.0-5.0). Results for the primary efficacy endpoint showed that five participants (1.5%) treated with DOR/ISL and one participant (0.6%) in the BIC/FTC/TAF group had a viral load of ≥50 copies/mL at Week 48, demonstrating non-inferiority of DOR/ISL to BIC/FTC/TAF (treatment difference 0.9%, 95% CI -1.9, 2.9). The superiority criteria were not met. Results for a secondary endpoint, the proportion of individuals with HIV-1 RNA <50 copies/mL at Week 48, showed that participants who switched to treatment with DOR/ISL or continued BIC/FTC/TAF maintained comparable rates of viral suppression at Week 48 (91.5% on DOR/ISL vs. 94.2% on BIC/FTC/TAF (treatment difference -2.6%, 95% CI -7.1, 2.6). No treatment-emergent resistance to DOR or ISL was observed. At Week 48, the mean percent change in total lymphocyte and CD4 counts were similar for DOR/ISL and BIC/FTC/TAF. There were identical rates of discontinuation for protocol-specified decreases in total lymphocyte and/or CD4 counts (two participants (0.6%) in the DOR/ISL group and one participant (0.6%) in the BIC/FTC/TAF group). Drug-related adverse events (AEs) and discontinuations due to drug-related AEs were similar between groups (n=35, 10.2% for DOR/ISL and n=16, 9.4% for BIC/FTC/TAF; n=4, 1.2% for DOR/ISL and n=2, 1.2% for BIC/FTC/TAF, respectively). Rates of toxicity grade 3 or 4 AEs and serious AEs were similar for DOR/ISL and BIC/FTC/TAF (n=25, 7.3% for DOR/ISL and n=13, 7.6% for BIC/FTC/TAF; n=15, 4.4% for DOR/ISL and n=11, 6.4% for BIC/FTC/TAF, respectively). Mean change in weight from baseline to Week 48 was minimal (-0.03 kg for DOR/ISL versus 0.28 kg for BIC/FTC/TAF; difference -0.30 kg, 95% CI -1.13, 0.53). The most common AEs (>6% in either study arm) were arthralgia, COVID-19, nasopharyngitis, and fatigue. One participant on DOR/ISL discontinued due to a drug-related serious AE (immune thrombocytopenia). There were two cases of low-level hepatitis B (HBV) viremia (HBV DNA <50 IU/mL) with no antigenemia or elevated transaminases in the DOR/ISL group and no cases in the BIC/FTC/TAF group; there were no cases of clinical HBV reactivation. About the Phase 3 data from MK-8591A-051 MK-8591A-051 is a Phase 3, open-label randomized, active-controlled, clinical trial evaluating the efficacy and safety of a switch to investigational, oral, once-daily DOR/ISL (100mg/0.25mg) in adults with HIV-1 infection that has been virologically suppressed using ART. The primary efficacy endpoint was percentage of participants with HIV-1 RNA ≥50 copies/mL at Week 48 (non-inferiority margin 4%). In this trial, 551 adults with HIV-1 RNA <50 copies/mL for three months or more on oral 2- or 3-drug ART, with no history of treatment failure and no known virologic resistance to DOR were randomized 2:1 and switched to DOR/ISL (n=366) or continued baseline antiretroviral therapy (bART) (n=185), stratified by bART regimen. The median age of participants was 51 years; 39.7% were assigned female sex at birth, 45.4% Black or African American and 14.5% Hispanic or Latine. At baseline, 64.2% were treated with an InSTI-based regimen, 30.3% with an NNRTI-based regimen, and 5.4% with a protease inhibitor (PI)-based regimen, with median duration on current ART of 3.8 years (IQR 2.0-6.3). Results for the primary efficacy endpoint showed that five participants (1.4%) in the DOR/ISL group and nine participants (4.9%) in the bART group had a viral load of ≥50 copies/mL at Week 48, demonstrating non-inferiority of DOR/ISL to bART (treatment difference -3.6%, 95% CI -7.8, -0.8). Results for a secondary endpoint, the proportion of individuals with HIV-1 RNA <50 copies/mL at Week 48, showed that participants who switched to treatment with DOR/ISL or continued bART maintained comparable rates of viral suppression at Week 48 (95.6% on DOR/ISL vs. 91.9% on bART; treatment difference 3.7%, 95% CI -0.3, 8.9). No treatment-emergent resistance to DOR or ISL was observed. Two participants discontinued DOR/ISL early after virologic failure at Week 4 with multiple resistance-associated mutations that were also present in baseline proviral DNA. These two participants were later found to be not eligible for the trial due to history of prior virologic failure and exclusionary DOR resistance. At Week 48, the mean percent change in total lymphocyte and CD4 counts were similar for DOR/ISL and bART. No participants discontinued treatment due to decrease in total lymphocyte and/or CD4 counts. In this open-label study, drug-related AEs were more commonly reported with DOR/ISL (n=44; 12.0%) than bART (n=9; 4.9%). Rates of toxicity grade 3 or 4 AEs and serious AEs were similar for DOR/ISL and bART (n=39, 10.7% for DOR/ISL and n=18, 9.7% for bART and n=23, 6.3% for DOR/ISL and n=9, 4.9% for bART, respectively). There were no drug-related serious AEs and there were no discontinuations due to serious AEs in the DOR/ISL group; there was one drug-related serious AE and two discontinuations due to serious AEs in the bART group. The most common drug-related AEs were diarrhea (DOR/ISL 3.3%, bART 0%), fatigue (1.9%, 0.5%), dizziness (1.9%, 0.5%), abdominal distention (1.6%, 0%), weight increased (1.6%, 0%), and headache (1.6%, 1.1%). Change in lipid parameters from baseline were similar between treatment groups for all bART strata. Mean change in weight from baseline to Week 48 was 0.94 kg for DOR/ISL and -0.18 kg for bART (difference -1.13 kg, 95% CI 0.31, 1.94). For baseline regimens without EFV or TDF, the difference in weight between DOR/ISL and bART was 0.82 kg (95% CI -0.22, 1.87). There was one case of low-level HBV viremia with no antigenemia or elevated transaminases in the DOR/ISL group and no cases in the bART group; there were no cases of clinical HBV reactivation. Indications and usage for PIFELTRO® (doravirine) and DELSTRIGO® (doravirine, lamivudine, and tenofovir disoproxil fumarate) 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 Virus (HBV) for DELSTRIGO 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. The effects of TDF-associated changes in BMD and biochemical markers on long-term bone health and future fracture risk in adults are unknown. 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 trials in combination with other antiretrovirals for the treatment of HIV-1. Trials with islatravir are designed to offer different dosing options as potential daily and once-weekly treatments. In addition to the MK-8591A-051 and MK-8591A-052 trials, ongoing Phase 3 trials of daily DOR/ISL (100mg /0.25mg) 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). 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, 2024 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.libproxy1.nus.edu.sg/product/usa/pi_circulars/p/pifeltro/pifeltro_pi.pdf and Patient Information for PIFELTRO at: https://www-merck-com.libproxy1.nus.edu.sg/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.libproxy1.nus.edu.sg/product/usa/pi_circulars/d/delstrigo/delstrigo_pi.pdf and Patient Information for DELSTRIGO at: https://www-merck-com.libproxy1.nus.edu.sg/product/usa/pi_circulars/d/delstrigo/delstrigo_ppi.pdf i bictegravir/emtricitabine/tenofovir alafenamide (BIKTARVY) is a registered trademark of Gilead Sciences, Inc. Media Contacts: Julie Cunningham (617) 519-6264 Deb Wambold (215) 779-2234 Investor Contacts: Peter Dannenbaum (732) 594-1579 Ayn Wisler (732) 594-0482