Panzyga (immune globulin intravenous, human - ifas) - 3 indications

Scroll down for additional information on each indication:

• for the treatment of primary immunodeficiency in patients two years of age and older and chronic immune thrombocytopenia in adults; approved in 2018
• for chronic inflammatory demyelinating polyneuropathy; approved February 2021

General Information

Panzyga is an immune globulin intravenous (human) - ifas 10% liquid preparation.

Panzyga is specifically indicated for the following:

• the treatment of primary humoral immunodeficiency (PI) in patients 2 years of age and older. This includes, but is not limited to, congenital agammaglobulinemia, common variable immunodeficiency, X-linked agammaglobulinemia, WiskottAldrich syndrome, and severe combined immunodeficiencies;
• for the treatment of adult patients with Chronic Immune Thrombocytopenia (ITP) to raise platelet counts to control or prevent bleeding;
• for the treatment of adults with chronic inflammatory demyelinating polyneuropathy (CIDP) to improve neuromuscular disability and impairment.

Panzyga is supplied as a solution for intravenous infusion. Scroll down for the recommended dosing/administration for each indication.

Mechanism of Action

Panzyga is an immune globulin intravenous (human) - ifas 10% liquid preparation. 

Treatment of PI: 

• Panzyga supplies a broad spectrum of opsonic and neutralizing IgG antibodies against bacteria or their toxins. The mechanism of action in PI has not been fully elucidated.

Treatment of ITP and CIDP in Adults : The mechanism of action of immunoglobulins in adults has not been fully elucidated.

Side Effects

Adverse effects associated with the use of Panzyga for primary immunodeficiency may include, but are not limited to, the following:

• headache
• nausea
• fever
• fatigue
• abdominal pain

Adverse effects associated with the use of Panzyga for chronic immune thrombocytopenia in adults may include, but are not limited to, the following:

• headache
• fever
• nausea
• vomiting
• dizziness
• anemia

Adverse effects associated with the use of Panzyga for chronic inflammatory demyelinating polyneuropathy in adults may include, but are not limited to, the following:

• headache
• fever
• dermatitis
• blood pressure increased

The Panzyga drug label comes with the following Black Box Warning: THROMBOSIS, RENAL DYSFUNCTION, and ACUTE RENAL FAILURE  Thrombosis may occur with immune globulin intravenous (IGIV) products, including Panzyga. Risk factors may include: advanced age, prolonged immobilization, hypercoagulable conditions, history of venous or arterial thrombosis, use of estrogens, indwelling vascular catheters, hyperviscosity, and cardiovascular risk factors. - Renal dysfunction, acute renal failure, osmotic nephropathy, and death may occur with the administration of IGIV products in predisposed patients. Renal dysfunction and acute renal failure occur more commonly in patients receiving IGIV products containing sucrose. Panzyga does not contain sucrose. - For patients at risk of thrombosis, renal dysfunction, or renal failure, administer Panzyga at the minimum infusion rate practicable. Ensure adequate hydration in patients before administration. Monitor for signs and symptoms of thrombosis and assess blood viscosity in patients at risk for hyperviscosity.

Indications 1 and 2 - for the treatment of primary immunodeficiency in patients two years of age and older and chronic immune thrombocytopenia in adults

approved in 2018

Dosing/Administration

Primary Humoral Immunodeficiency (PI):

• Dose: 300 to 600 mg/kg body weight (3-6 mL/kg) administered every 3 to 4 weeks
• Initial Infusion Rate (first 30 min): 1 mg/kg/min (0.01 mL/kg/min)
• Maximum Infusion Rate (as tolerated): 14 mg/kg/min (0.14 mL/kg/min)

Chronic Immune Thrombocytopenia (ITP):

• Dose: 2 g/kg (20 mL/kg), divided into 2 daily doses of 1 g/kg (10 mL/kg) given on 2 consecutive days
• Initial Infusion Rate (first 30 min): 1 mg/kg/min (0.01 mL/kg/min)
• Maximum Infusion Rate (as tolerated): 8 mg/kg/min (0.08 mL/kg/min)

Clinical Trial Results

The FDA approval of Panzyga for PI was based on NGAM-01, a Phase 3 efficacy study in adults and children with PI aged ≥2 years (N=51). The primary endpoint was the number of serious bacterial infections (SBI) experienced by subjects over 12 months of exposure to Panzyga. Subjects received Panzyga via IV infusion at a dose between 200 to 800 mg/kg body weight for one of two treatment intervals (i.e., every 3 or 4 weeks), consistent with the subject’s previous dosage regimen. Subjects participated in the study for a mean of 360 days. Infusions were initiated at a rate of 1 mg/kg/min for the first 30 minutes, and, if tolerated, could be advanced to a maximum tolerated rate not exceeding 4 mg/kg/min. NGAM-01 met its primary efficacy endpoint (SBI rate). The observed rate was 0.08 serious bacterial infections per patient per year (4 infections over 50.2 patient-years). 

The FDA approval of Panzyga for chronic primary ITP was based on NGAM-02, a Phase 3 study in adults aged ≥18 years (N=40) with chronic primary ITP. Subjects were enrolled if they had a history of chronic ITP with a platelet count of less than or equal to 20x 109 /L with or without bleeding manifestations.  Panzyga was administered at a dose of 1gm/kg/day for two consecutive days and subjects were followed-up for safety through Day 63. The primary endpoint was platelet response rate, defined as the proportion of enrolled subjects meeting eligibility criteria who demonstrated an increase in platelet count to ≥50 x 109/L within 7 days after the first infusion. The NGAM-02 trial met its primary efficacy endpoint as 29/36 enrolled subjects (81%;) responded to Panzyga. Median time to response was 2 days and duration of response was 14 days. 80% (23/29) of subjects with a response attained a normal platelet count. For the 36 efficacy-evaluable subjects, mean maximum platelet count after the start of treatment was 237x109 /L.

Indication 3 - for chronic inflammatory demyelinating polyneuropathy

approved February 2021

Dosing/Administration

• Loading Dose: 2 g/kg (20 mL/kg), divided into 2 daily doses of 1 g/kg (10 mL/kg) given on 2 consecutive days
• Maintenance dose: 1-2 g/kg (10-20 mL/kg) every 3 weeks divided in 2 daily doses given over 2 consecutive days
• Initial Infusion Rate (first 30 min): 1 mg/kg/min (0.01 mL/kg/min)
• Maximum Infusion Rate (as tolerated): 12 mg/kg/min (0.12 mL/kg/min

Clinical Trial Results

The FDA approval of Panzyga for CIDP was based on data from a prospective, double-blind, randomized, multi-center Phase 3 study in 142 patients diagnosed with CIDP.  Efficacy, safety, and tolerability was observed during seven maintenance infusions at three-week intervals over a six-month period. The primary efficacy endpoint was the proportion of responders in the 1.0 g/kg Panzyga treatment arm at six months relative to baseline. A responder was defined as a patient with a decrease of at least one point in the adjusted 10-point Inflammatory Neuropathy Cause and Treatment (INCAT) disability score. The primary endpoint was met with 80% of patients in the study achieving an INCAT response with the 1.0 g/kg dose. Dose-dependent efficacy was shown by several supporting endpoints, including a 92% response in adjusted INCAT score in the 2.0 g/kg dose arm. Dose-dependent responses were also demonstrated in the 1.0 g/kg and 2.0 g/kg dose arms in grip strength, Inflammatory Rasch-built Overall Disability Scale (I-RODS) and Medical Research Council (MRC) sum scores.