Safety, Tolerability, and Efficacy of NVG-2089 in Participants With Immune Thrombocytopenia

Inclusion Criteria:

• Males and female participants, age 18 to 80 years at time of screening.

• Diagnosis of persistent (>3 months and ≤12 months), or chronic (>12 months) primaryITP. If the participant has received prior treatment for ITP, they must have ahistory of response to at least one previous therapy (defined as increase inplatelet count to ≥ 50,000 cells/mm3 with an increase of ≥ 20,000 cells/mm3 relativeto platelet count prior to treatment).

• Asymptomatic or with minor mucocutaneous bleeding AND platelet count of ≥ 20,000 to ≤50,000 cells/mm3, measured on 2 occasions. At least one measurement should beobtained during screening. Documented historical platelet count obtained within 4weeks prior to screening will also be acceptable for one of the two readings.

• (For US only) If at least one screening platelet count >30,000 cells/ mm3 and <50,000 cells/mm3, the participant must be on at least 1 other treatment for ITPwith insufficient response as evidenced by platelet count <50,000 cells/ mm3.

• If participant has received prior IVIg therapy participant must have shown asufficient platelet response (doubling from baseline platelet count within 7 days ofIVIg infusion) and must not have lost response to IVIg therapy while on treatment.

• Female participants of childbearing potential must have a negative serum pregnancytest at Screening and a negative urine pregnancy test on Day 1.

• Female participants who are sexually active with a male partner of reproductivepotential must use double contraception (including a barrier contraceptive andanother method) from at least 28 days prior to Screening and for 90 days after lastdose of study drug; female participants must also refrain from oocyte donation forthe purpose of reproduction during this period. Exceptions are made for surgicallysterile participants, or post-menopausal females (defined as 12 months ofspontaneous amenorrhea or 6 months of spontaneous amenorrhea with serum follicle -stimulating hormone levels >40 mIU/mL or 6 weeks postsurgical bilateraloophorectomy with or without hysterectomy). Abstinence is acceptable if this is theusual lifestyle and preferred contraception for the participant.

• Male participants with female partners who are of reproductive potential must agreeto the use of highly effective, barrier contraception for the duration of the study,and for 90 days after the last dose of study drug.

• Participant is capable or has a legally authorized representative(s) (LAR[s])capable of providing a signed informed consent which includes compliance with therequirements and restrictions listed in the ICF.

Exclusion Criteria:

• Secondary forms of ITP (e.g., ITP secondary to infection, autoimmune diseases,lymphoproliferative diseases and medications).

• History of splenectomy.

• History of malignancy, unless the participant received treatment with curativeintent. Participants with fully excised non-melanoma skin cancer or cervical cancerare allowed.

• History of solid organ transplant.

• Planned or anticipated medical or surgical procedure, including dental procedure,during the timeframe of the study conduct.

• Clinically significant active or chronic uncontrolled bacterial, viral, or fungalinfection at screening, including active viral infection at screening.

• Any medical condition that, in the opinion of the investigator, would interfere withstudy evaluations or procedures, and/or put the participant at increased risk.

• ECG findings of QTcF > 450 msec (males) or > 470 msec (females), poorly controlledatrial fibrillation or other clinically significant abnormalities.

• Other significant organ dysfunction, including but not limited to, hematologic,renal, or hepatic dysfunction, as evidenced by:

1. Absolute neutrophil count ≤ 1.5 x 109 /L

2. Hemoglobin (Hgb) < 9 g/dL

3. Aspartate aminotransaminase (AST) and/or alanine aminotransferase (ALT) ≥ 2 xthe upper limit of normal (ULN),

4. Albumin ≤ 3 g/dL

5. Total bilirubin ≥ 1.5 x ULN

6. Estimated glomerular filtration rate < 50 mL/min/1.73m2 using the ChronicKidney Disease Epidemiology Collaboration (CKD-EPI) method

• Any of the following at screening:

1. Active Hepatitis B Virus (HBV): Hepatitis surface antigen (HBsAg) positive

2. Active Hepatitis C Virus (HCV): serology positive for HCV-antibody

3. Human Immunodeficiency Virus (HIV) positive serology

• Transfusion of blood, blood products (including immune globulin), or plasmapheresiswithin 4 weeks prior to screening.

• Change in current ITP therapy (e.g., prednisone, methylprednisone, mycophenolate,dapsone, danazol, azathioprine, or TPO receptor agonist) or dose within 4 weeksprior to screening.

• Receipt of dexamethasone within 4 weeks prior to screening.

• Receipt of rituximab or an anti-CD20 agent within 6 months prior to screening.

• Receipt of an neonatal Fc receptor (FcRn) inhibitor within 12 weeks prior toscreening.

• Receipt of IVIg within 4 weeks prior to screening.

• Receipt of another investigational drug within 4-weeks or 5 half-lives (whichever islonger) prior to screening.

• Concurrent treatment with other monoclonal antibody and/or Fc therapies.

• Current or past history (within 12 months of screening) of alcohol, drug, ormedication abuse. Positive urine drug screen at screening visit.

• Pregnant or lactating women and those intending to become pregnant during the studyor are unwilling to apply an effective birth control method (such as implants,injectables, combined oral contraceptives, intrauterine devices [IUDs], sexualabstinence, or vasectomized partner) up to 90 days after last study drugadministration.

• Poor venous access.

• A known allergy to study drug and/or any of its components.