Phase 1a/b Tolerability of NTR-1011 in Healthy Adults and Adult Patients With SLE and RA

Phase 1a - Healthy Volunteers (Completed, No Longer Enrolling) Key Inclusion Criteria * Healthy men and women, 18-55 years of age * Body mass index (BMI) between 17.0 and 30.0 kg/m² * Good general health, confirmed by medical history, physical exam, vital signs, ECG, and lab testing * Willing and able to use highly effective contraception during and after the study Key Exclusion Criteria * Pregnant or breastfeeding * History of drug allergies or anaphylaxis to human, murine, or yeast proteins, monoclonal antibodies, or other allergens * Use of an investigational drug within 30 days (or 5 half-lives) before dosing * Positive test for hepatitis B, hepatitis C, or HIV * Clinically significant heart, lung, digestive, blood, autoimmune, psychiatric, or other medical condition * Clinically significant abnormal lab values (e.g., liver enzymes, blood counts) or ECG findings * Uncontrolled high blood pressure * Poor venous access Phase 1b - Adult Patients with SLE and RA (Actively Recruiting) General Inclusion Criteria (All Patients) * Men and women, 18-75 years of age * Able to understand and sign informed consent, and comply with study visits * Willing and able to use highly effective contraception during and after the study Additional Inclusion Criteria - SLE Patients * Diagnosis of SLE for at least 6 months, meeting 2019 EULAR/ACR classification criteria * Active disease at screening * Positive lupus-related antibodies (e.g., anti-dsDNA, anti-Smith) and low complement (C3/C4) * On stable standard-of-care background therapy (e.g., antimalarials, low-dose corticosteroids, and at least one conventional DMARD) * Up to date on age-appropriate vaccinations Additional Inclusion Criteria - RA Patients * Diagnosis of RA for at least 3 months, meeting 2010 ACR/EULAR classification criteria * Moderate-to-severe active disease * Seropositive for rheumatoid factor and/or anti-CCP antibodies * On stable standard-of-care background therapy (e.g., low-dose corticosteroids and at least one conventional DMARD) Key Exclusion Criteria (All Patients) * Pregnant or breastfeeding * Known allergy or reaction to NTR-1011, placebo components, or related products * Use of an investigational drug within 30 days (or 5 half-lives) before dosing, or concurrent enrollment in another clinical trial * History of cancer within the past year (with limited exceptions) * Significant kidney impairment, severe liver dysfunction, or severe lung disease * Uncontrolled high blood pressure or significant cardiovascular disease (e.g., recent heart attack or stroke, certain arrhythmias) * Active, recurrent, or high-risk infection, including active or latent tuberculosis without appropriate treatment, opportunistic infections, or chronic hepatitis B * Recent symptoms of COVID-19 without a documented negative test * Receipt of a live vaccine within 4 weeks before screening or planned within 4 weeks after last dose * Significant central nervous system disease or pain-amplification conditions (e.g., epilepsy, fibromyalgia) that could interfere with study assessments * Major surgery within 8 weeks before screening or planned within 6 months after baseline * History of bone marrow, stem cell, or solid organ transplant (except cornea) * Uncontrolled diabetes within the past 12 months (with some exceptions) * History of a blood clot within the past 12 months (with some exceptions) * Clinically significant abnormal lab values (e.g., liver enzymes, blood counts) at screening