Lexicon Bets on Sotagliflozin in HCM as T1D Relaunch Faces DKA Headwinds

Lexicon Provides Key Clinical Updates and Q2 2026 Financials

Lexicon Pharmaceuticals reported its second quarter 2026 financial results, alongside significant clinical and corporate updates. The company announced the completion of enrollment for its pivotal Phase 3 SONATA-HCM study of sotagliflozin for hypertrophic cardiomyopathy, with top-line data expected in Q1 2027. Lexicon is also nearing the resubmission of its New Drug Application for ZYNQUISTA in type 1 diabetes, anticipated in Q4 2026, supported by safety data from the STENO1 study. Financially, Lexicon reported total revenues of $0.7 million and a net loss of $31.8 million for Q2 2026, ending the quarter with $190.6 million in cash and investments.

• Lexicon has completed enrollment for its Phase 3 SONATA-HCM study of sotagliflozin, exceeding its target of 500 patients. This placebo-controlled trial is evaluating sotagliflozin in both non-obstructive and obstructive HCM, with a substantial majority of patients having nHCM, addressing a significant unmet need. Top-line results are anticipated in the first quarter of 2027, marking a crucial step towards a novel treatment option for this condition.
• The company is actively preparing for the resubmission of its New Drug Application (NDA) for ZYNQUISTA (sotagliflozin) for glycemic control in adults with type 1 diabetes. This effort is supported by safety data from the third-party funded STENO1 study, which is meeting the patient exposure and safety data requirements identified by the U.S. FDA. Lexicon expects to resubmit the NDA in the fourth quarter of 2026, aiming to bring a new treatment option beyond insulin to this patient population.
• Lexicon's pipeline includes LX9851, a first-in-class ACSL5 inhibitor, which is in Phase 1 development by licensee Novo Nordisk for obesity and metabolic disorders. This collaboration includes an upfront payment of $45 million and potential milestone payments up to $1 billion. The company also reported its Q2 2026 financials, with $0.7 million in revenues and a net loss of $31.8 million, while maintaining a strong cash position of $190.6 million as of June 30, 2026, bolstered by a new $100 million loan facility.

Unpacking SONATA-HCM: A Pivotal Trial for Hypertrophic Cardiomyopathy

The therapeutic landscape for hypertrophic cardiomyopathy (HCM) has been reshaped by pivotal clinical trials investigating novel mechanisms of action. These studies have primarily focused on cardiac myosin inhibitors and other agents to address the distinct pathophysiologies of both obstructive (oHCM) and non-obstructive (nHCM) forms of the disease. The following summary outlines the key design parameters, endpoints, and high-level outcomes from these influential trials.

Sotagliflozin's Expanding Role in Cardiometabolic Disorders

Beyond its investigation in hypertrophic cardiomyopathy, sotagliflozin—the first dual SGLT1/SGLT2 inhibitor—has been evaluated across a broad range of cardiometabolic and metabolic indications, reflecting its distinctive mechanism of combined intestinal glucose absorption delay and renal glucose reabsorption inhibition. Its clinical development spans type 1 and type 2 diabetes, heart failure, chronic kidney disease, and several exploratory areas, supported by a mix of large-scale RCTs, mechanistic crossover studies, and preclinical models.

• Type 1 Diabetes Mellitus (T1DM): Studied as an adjunct to optimized insulin therapy in the phase 3 inTandem1 and inTandem2 trials (NCT02384941, NCT02421510) and a related 52-week, double-blind, placebo-controlled trial (200 mg and 400 mg doses, n=782). Sotagliflozin significantly reduced HbA1c, fasting plasma glucose, weight, and total daily insulin dose, while improving treatment satisfaction and reducing diabetes distress. It is EU-approved as an insulin adjunct for T1DM patients with BMI ≥27 kg/m² and inadequate glycemic control, though the FDA issued a Complete Response Letter due to DKA concerns. A meta-analysis of 12 RCTs (14–52 weeks) also showed reduced cardiovascular disease and end-stage kidney disease risk, alongside increased genital infections but fewer fractures versus control.

• Type 2 Diabetes Mellitus (T2DM): Being developed by Lexicon Pharmaceuticals and Sanofi, with pivotal phase 3 trials SOLOIST-WHF and SCORED demonstrating significant reductions in cardiovascular and heart failure events (HR 0.67 and 0.74, respectively). A meta-analysis of nine studies (n=15,320; median follow-up 13.4 months; PROSPERO CRD42023432732) confirmed reduced risk of heart failure, stroke, and MACE, along with modest systolic blood pressure reduction, but increased risk of genital mycotic infection, diarrhea, and volume depletion. Intervention models across these trials were predominantly randomized, double-blind, placebo-controlled, parallel-group, multicenter designs; a separate 52-week phase 3 trial in stage 4 CKD used a 1:1:1 randomized, placebo-controlled parallel design (200 mg vs. 400 mg vs. placebo, n=277).

• Heart Failure (HF): Sotagliflozin is approved as the first dual SGLT1/2 inhibitor for HF management. The SOLOIST-WHF trial (NCT03521934) was a multicenter, double-blind, randomized, placebo-controlled trial in 1,222 patients with T2DM recently hospitalized for worsening HF, using total cardiovascular deaths and HF hospitalizations/urgent visits as the primary endpoint, with KCCQ-12 score as a prespecified secondary outcome. Although pivotal trials required a T2DM diagnosis, the approved indication is broader, expanding treatment options for HF patients generally.

• Type 2 Diabetes with Chronic Kidney Disease and Cardiovascular Risk: The SCORED trial specifically enrolled T2DM patients with CKD and cardiovascular risk factors, again employing a randomized, double-blind, placebo-controlled parallel design, and demonstrated a significant reduction in cardiovascular events (HR 0.74).

• Myocardial Infarction (Preclinical): An animal model study in Sprague Dawley rats used left anterior descending coronary artery ligation (or sham) followed by random assignment to sotagliflozin (10 mg/kg) or vehicle via intraperitoneal injection, assessing cardiac function via echocardiography and histological/molecular markers of remodeling and inflammation at 14 days post-MI.

• Dyslipidemia and Steatohepatitis (Preclinical): Investigated in mouse models using oral fat tolerance tests, a Triton-induced hypertriglyceridemia model, and chronic treatment in high-fat diet-induced obese mice, suggesting potential therapeutic utility in diabetic dyslipidemia and steatohepatitis.

• Sepsis-Related Myocardial Injury (SRMI, Preclinical): An in vitro study in H9C2 rat cardiomyocytes used LPS challenge with sotagliflozin treatment (10, 20, and 30 μM), combined with label-free quantitative LC-MS/MS proteomics, revealing cardioprotective effects and repurposing potential for SRMI.

• Type 3 Diabetes / Alzheimer's Disease (Exploratory): A molecular docking study examined sotagliflozin's dual binding to SGLT2 and human brain acetylcholinesterase (AChE), suggesting potential relevance for Alzheimer's disease and supporting future scaffold-based drug design for type 2/type 3 diabetes.

• Thrombosis (Mechanistic Study): The SOTA-THROMBOSIS trial is a randomized, crossover study in 16 healthy volunteers comparing the antithrombotic effects of dual SGLT1/2 inhibition (sotagliflozin) versus selective SGLT2 inhibition (empagliflozin), with each treatment administered for 4 weeks separated by a one-month washout period, allowing each participant to serve as their own control.

Addressing Key Unmet Needs in Hypertrophic Cardiomyopathy

Despite recent therapeutic advances, significant unmet needs persist in the management of hypertrophic cardiomyopathy (HCM), affecting both clinical outcomes and quality of life. Even with treatment, patients continue to experience a substantial symptom burden, and critical gaps remain in the treatment of specific subpopulations, risk stratification, and equitable access to specialized care.

• Persistent Clinical and Quality of Life Burden: Patients with HCM continue to face a significant symptom burden, high healthcare resource utilization (HCRU), and diminished health-related quality of life (HRQoL) despite intervention. Studies report that 25.8% of patients experience HCM-related hospitalizations, with rates increasing alongside NYHA class. This burden translates to an overall work impairment of 16.1% and activity impairment of 26.6%, underscoring the impact on daily life.

• Therapeutic Gaps for Non-Obstructive HCM (nHCM): A primary unmet need is the lack of approved, disease-specific therapies for nHCM, which accounts for approximately 30-70% of cases. While cardiac myosin inhibitors have been approved for obstructive HCM (oHCM), patients with the non-obstructive phenotype are limited to conventional pharmacotherapies that are often poorly tolerated, inadequate, and not targeted to the underlying pathophysiology.

• Suboptimal Risk Stratification and Diagnosis: Accurately identifying patients at high risk for sudden cardiac death (SCD) remains a major clinical challenge, particularly for intermediate-risk individuals and specific groups such as those who have undergone septal reduction therapy. Furthermore, HCM remains underdiagnosed, with issues like left ventricular outflow tract (LVOT) obstruction not always being well-characterized by standard echocardiography, highlighting the need for improved detection and screening methods.

• Socioeconomic and Care Delivery Disparities: Evidence points to significant disparities in outcomes based on socioeconomic factors. Patients residing in areas with lower median household incomes or a worse social deprivation index (SDI) face an independently higher risk of adverse clinical events, including heart failure and ventricular arrhythmias. These gaps are compounded by a lack of dedicated HCM teams and geographic disparities in access to specialized care centers.

• Limitations of Novel Therapies: While promising, new cardiac myosin inhibitors like mavacamten are constrained by a narrow therapeutic window, the risk of reversible reductions in ejection fraction, and the need for frequent imaging and safety surveillance. The high cost of these treatments and the logistical burden of monitoring present additional challenges to their widespread implementation.