Gamunex-C: The Immune Supplement
Gamunex C is a type of sterile antibody solution that is extracted from human beings. Injections of this very solution are given to patients suffering from a weak immune system or immune disorder to help them combat infections.
What Is Gamunex-C?
Generic Name: Immune globulin intravenous (human), 10% Caprylate/Chromatography Purified 10% Liquid Preparation
Brand Name: Gamunex-C
Class Of Drug: Immune globulins
As the name indicates, Gamunex-C is a combination of immune globulins (antibodies) that is used as a treatment for patients suffering from immunodeficiencies. There are a number of conditions where patients lack an optimally working immune system that produces antibodies to keep them safe from microorganism attacks.
In such cases, Gamunex-C acts as an external source of antibodies that can boost the immune performance of the body.
What Is Inside Gamunex-C?
An injection of Gamunex-C contains purified immunoglobulins (Ig) that are made from large pools of human plasma by a combination of cold ethanol fractionation, caprylate precipitation, and filtration, and anion-exchange chromatography. Isotonicity is achieved by the addition of glycine
Is Gamunex-C Safe?
Yes, Gamunex-C is a well-tolerated sterile solution of immunoglobulins. As per a study, intravenous immunoglobulin preparation i.e. IGIV-C (Gamunex, 10%) has good pharmacokinetics and good tolerability.
Does Gamunex-C Increase Sugar Levels?
Is there a link between Gamunex-C usage and a rise in sugar levels? It is clearly indicated by the FDA, that Gamunex-C does not contain sucrose (which is a type of sugar). Unlike most antibody preparations, this sterile solution is free of sucrose.
Therefore, Gamunex does not increase sugar levels!
Does Gamunex-C Cause Weight Gain?
Another frequently asked question is “Does Gamunex C usage cause weight gain?”
Well, the answer is “No” for a normal person having optimally working kidneys.
However, in cases where kidney function is compromised, there is a chance that you might experience serious kidney disease that can cause sudden unexplained weight gain. But this weight is indicative of underlying kidney disease and not due to Gamunex C infusion.
How Does Gamunex-C Work?
Gamunex C is administered via the Intravenous or the subcutaneous route. Whatever route it takes, the antibodies (immune globulins) in the solution are delivered into the body. These antibodies recognize and fight against harmful bacteria/other microorganisms.
In cases of auto-immune diseases, the healthy antibodies from the injection block the body’s immune system from attacking the body’s cells. This results in a reduction of cell death and inflammation caused by the auto-antibodies, thereby, providing relief from symptoms.
Gamunex-C is commercially available in vials form of 1g, 2.5g, 5g, 10g, 20g, and 40g. It is supposed to have a shelf-life of 3 years but only if the vial is kept between 2-8 ℃ i.e. 36-46 ℉ from the date of manufacture.
Does Gamunex-C Need To Be Stored In A Refrigerator?
The solution must be stored in the fridge for long-term usage. However, it can be stored at room temperature not to exceed 25℃ for up to 6 months. After the specified period, the product must be discarded.
Note: It should be kept in mind that the temperature must not exceed this value. Do not freeze Gamunex-C and discard any frozen solution.
Gamunex-C is indicated as a treatment modality for the following conditions:
Primary Immunodeficiency (PI)
Primary humoral immunodeficiency (PI) is a condition characterized by frequent infections caused by a deficiency of some classes of immunoglobulins.
Gamunex-C is primarily indicated for conditions like Primary immunodeficiency diseases (PID). IVIg therapies i.e. intravenous immune globulins are effective in the treatment of immunodeficiencies. The most evident IVIg(s) include Privigen, Gammaked, Gammaplex, Hizentra, and Gamunex-C.
As per research, immunoglobulin replacement therapy is critical in many PIDs affecting antibody production. Hence, Gamunex-C is crucial for young patients suffering from the disorder. Immunoglobulin replacement therapy (Gamunex-C) was found to be effective for both adults and children with primary immunodeficiency diseases.
Pediatric PID patients can also benefit from IgG therapy via Gamunex-C infusion.
Immunoglobulin therapy has shown promising results in alleviating symptoms of congenital agammaglobulinemia such as
- Otitis media
IgG replacement in patients suffering from X-linked agammaglobulinemia can make life easier by imparting symptomatic relief. As per a study, a median dose of 397 mg/kg IVIg was sufficient for keeping the children free of infections.
This treatment strategy also reduces the incidence of pneumonia and hospital admission in patients with Agammaglobulinemia
Eczema (red, irritated skin) is seen in this disease due to abnormal/nonfunctional immune system cells i.e. white blood cells.
Idiopathic Thrombocytopenic Purpura (ITP)
Intravenous immunoglobulin treatment can work for ITP. Studies show that Gamunex for Idiopathic Thrombocytopenic purpura can improve the prognosis and help alleviate symptoms.
A randomized controlled trial concluded that starting intravenous immunoglobulin therapy early on for newly diagnosed idiopathic thrombocytopenic purpura patients can be a fruitful step.
Chronic Inflammatory Demyelinating Polyneuropathy (CIPD)
Intravenous immune globulin (10% caprylate-chromatography purified) i.e. Gamunex-C was found to be the best treatment option for the management of chronic inflammatory demyelinating polyneuropathy in a trial. The administration of Gamunex-C leads to significant improvement in disability scores. Improvements in grip strength (in both hands) were experienced by the participants too.
The healthy antibodies from Gamunex-C block the immune and inflammatory processes that destroy the myelin sheath leading to improvement of symptoms.
You can see results as soon as 3 weeks from the start of therapy. Research has found IVIg therapy to be effective in improving motor symptoms of CIPD.
The dire need of the hour is treatment against the infamous COVID-19. Individuals suffering from immune system disorders are more prone to falling prey to COVID-19 infection. It was found in a 2020 study that Gamunex-C contains antibodies that are effective against SARS-CoV-2 antigens.
It is also believed that high doses of IVIg (Gamunex-C) can improve symptoms in children suffering from severe case coronavirus infection. However, there is a lack of strong evidence to approve of its safety and tolerability.
A Chinese report noted that early administration of IVIg is beneficial in improving symptoms of immunodeficiency. In addition to its role in immunodeficient patients, the immune globulins can be cross-reactive with COVID-19.
Contraindications Of Gamunex
Gamunex-C infusion is contraindicated in the following cases:
History Of Thrombosis
All immunoglobulins are protein in nature. This biological nature of the Ig therapy makes the receiver prone to developing thrombosis. This is why the greatest adverse effect associated with antibody therapy is thrombosis.
Therefore, people who have suffered thrombosis or are at a risk should not receive Gamunex-C infusion. The risk factors include:
- High levels of cholesterol in the body
- Family history of arterial thrombosis
- Poor diet
Presence Of Underlying Cardiovascular Disease
As thrombosis is a likely adverse outcome of IVIg therapy, patients having underlying heart issues should not take the therapy. Use caution when administering to patients age 65 years and over
Some antibodies contain high quantities of sodium. Therefore, such solutions should be used cautiously in patients with cardiac conditions and hypertension.
Blood Circulatory And Renal Disorder
Another lot of patients that should not go for any IVIg therapy, be it Gamunex-C, include patients suffering from blood circulatory disorders.
Kidney problems are seen with human immune globulin. In some cases, the results can be devastating and even lead to death. This is especially true for IVIg therapies that contain sucrose. As Gamunex does not contain sucrose it is relatively safer for the general public.
However, patients with compromised renal function must stay away from Gamunex-C as it can cause osmotic nephropathy.
Gamunex-C is contraindicated in IgA deficient patients with antibodies against IgA and a history of hypersensitivity.
Another review found that anti-IgA antibodies are associated with the development of adverse reactions to intravenous immunoglobulin infusion in patients.
Individuals that have a hypersensitive allergic response to transfusions must not try any sort of IVIg therapy. This is because anaphylactic reactions are seen after the administration of gamma globulins.
Injection of immune globulin 10% caprylate can be given into a vein or under the skin. This means Gamunex-C can be given as an IVIG infusion or a subcutaneous infusion.
For Iv infusion, Gamunex is given just like other IVIg therapies. IV route is used for the treatment of primary immunodeficiencies (PI), Immune thrombocytopenic purpura (ITP), and Chronic inflammatory demyelinating polyneuropathy (CIDP).
Note: You should not inject Gamunex-C intravenously if your doctor has instructed the subcutaneous pathway for you.
A Gamunex-C infusion pump is used to inject the solution. You have to fill the pump reservoir and prepare the infusion pump. Subcutaneous infusion can be given at different sites of the body at the same time.
Gamunex-C Infusion Protocol
- The length of the infusion time depends on the condition being treated.
- You must follow the doctor’s instructions if infusing Gamunex-C at home.
- Gamunex-C must be given slowly (IV or subcutaneous).
- Do not shake the medication bottle.
- Prepare a dose only when you are absolutely ready to get the injection (immediate use).
- Do not mix other medications with Gamunex-C (in the same infusion).
- Get frequent blood tests to check for antibody titers.
- The vial is designed for single-use, discard the vial after usage.
- Do not freeze Gamunex-C.
- Do not inject Gamunex-C yourself if you do not fully understand the procedure.
- Do not administer subcutaneously for CIPD and ITP patients.
- Do not inject Gamunex-C into a blood vessel (in case of subcutaneous infusion).
The administration tubing and Y-site connection tubing are used if needed. You can also use several different catheters for different sites. Your healthcare provider will inform you about the best sites for subcutaneous Gamunex-C infusion.
All the items i.e. needle, catheter, and tubing are designed for one-time use only and must be discarded after usage.
Goals In Administration Of Gamunex-C
Dosage And Gamunex Infusion Rate
As per FDA guidelines, the Infusion rate of Gamunex-C for PI must be as follows:
|Route of Administration||Dose||Initial Infusion Rate||Maintenance Infusion Rate|
|IV (Intravenous)||300-600 mg/kg||1 mg/kg/min||8 mg/kg/min
Every 3 to 4 weeks
|Subcutaneous (SC)||1,37 x current IV dose in grams/IV|
Dose interval in weeks
|Adult: 20 mL/hr/site|
Pediatric: 10 mL/hr/site to 15 mL/hr/site
10 mL/hr/site to 20 mL/hr/site
Infusion rate for ITP and CIPD should be as follows:
|Indication||Dosage||Initial Infusion Rate||Maintenance Infusion Rate|
|ITP||2 g/kg||1 mg/kg/min||8 mg/kg/min|
|CIPD||Loading dose 2 g/kg|
Maintenance dose 1 g/kg
|2 mg/kg/min||8 mg/kg/min
Every 3 weeks
Note: The above-mentioned infusion rates (as maintenance infusion) are valid only if the values are well tolerated.
Precautions Of Use
Gamunex-C should be used cautiously in the following people:
1. Pregnant Women
Studies suggest the IVIg therapy is beneficial for pregnant mothers especially for ladies that suffer from recurrent pregnancy loss (RPL). But injected antibodies might interfere with fetal growth, therefore, they should be used with caution in pregnant women.
2. Lactating Mothers
There is no information regarding the presence of GAMUNEX-C in human milk even though there is a study suggests that IgG is a natural component of breast milk, therefore it should be used with caution in lactating women,
Cost Of Gamunex-C
The price of Gamunex-C varies from pharmacy to pharmacy but on average 10 mL of Gamunex-C (10%) injectable solution costs around $150. The 10 mL dosage is available for 145$ while the 25 mL and 50 mL preparations will cost you almost 350$ and 690$ respectively.
Copay assistance and financial support programs for Gamunex-C are also offered by different companies. With these programs, you can save up to $2500 over a period of 1 year (12 months).
You can benefit from the patient assistance programs if suffering from CIDP, PIDD or other indicated conditions for Gamunex usage.
You should discontinue using Gamunex C and call your doctor if you experience the following signs (of thrombosis):
The following signs are usually seen on the site of infusion (and other sites of the body too):
- Redness and itching of the skin
- Formation of blisters
- Swelling of the orofacial region (mouth, lips, face, tongue, etc.)
- Breathing difficulties
Renal Function Disruption
IVIg and subcutaneous administration of Gamunex-C can compromise renal function. The initial signs of this disturbance include:
- Inability to urinate
- Changes in urine color and quantity
You must inform your doctor of these warning signs as soon as possible.
Changes In Blood Pressure
Hypotension or fall of blood pressure can occur following Gamunex-C infusion. A hike in blood pressure is also observed in some patients. If you experience headache or dizziness following the Ig infusion, then stop the infusion and refer to a doctor.
Gamunex-C infusion might take a toll on your lungs. Therefore, you should inform your doctor about any breathing issues like shortness of breath or difficulty breathing without any ado.
Fever And Fatigue
Fatigue and fever after Gamunex-C usage must be reported.
Symptoms such as seizures and delirium (feeling confused) must not be neglected and reported earliest possible.
Side Effects Of Gamunex
Gamunex-C is generally a well-tolerated and safe solution to be injected in the vein or under the skin. However, there are some side effects associated with its use that range from a mild rash to serious life-threatening issues such as renal failure.
Other Side Effects
Most of the side effects occur on the infusion site and can be managed. The most commonly encountered non-serious side effects of Gamunex-C are discussed below:
- Rash on skin that may be accompanied by redness and bruising
- Itching on the injection site
- Pain/stiffness on infusion site
- Runny nose and sore throat (with cough)
- Lethargy and bad moods
- Back Pain (and muscle/joint pain)
According to a study, the most common effects seen with 10% IVIg caprylate solution were headache, pyrexia (fever), pulmonary embolism, and vomiting.
Serious Side Effects
The most serious adverse effects of Gamunex-C are discussed below:
There is a great risk of thromboembolism i.e. formation of a blood clot following IVIg infusion. IVIg 10% caprylate usage has a high chance of developing a thrombus in your body, especially if you are already suffering from atherosclerosis (or are obese).
Thrombosis was not affected by any prophylactic management in a study and is therefore considered a risk associated with Gamunex-C. This blood clot formation can eventually lead to complications such as heart attack, stroke, and heart failure, etc.
Therefore, the trick is to keep the patient hydrated, start with a low dose, and keep the infusion rate to the lowest possible.
Intravenous infusion of the antibody solution can put your kidneys at risk. Research has identified acute renal failure as an evident adverse reaction caused by intravenous immunoglobulin therapy.
Kidney compromise caused by immune globulin products such as Gamunex-C may present as edema in the peripherals of the legs, decrease in urination, sudden weight gain, and shortness of breath.
Dehydration is also an unwanted outcome of immune globulin therapy.
Serious inflammation of the meninges of the brain can put your life at risk. Aseptic meningitis is associated with IVIg therapy. A study suggests that it seldom happens and is found in the transient form.
Hemolysis (and Anemia)
Breakdown of red blood cells following IVIg infusion can lead to the development of anemia which is a serious complication of Gamunex-C.
Do not administer GAMUNEX-C subcutaneously in patients with ITP because of the risk of formation of a blue/black wound (pocket of blood) known as a hematoma.
Transmission Of Infections
As this is an infusion extracted from human blood, there is a possibility of transfer of harmful viruses such as variant Creutzfeldt-Jakob disease(vCJD), etc
Gamunex Drug Interactions
Gamunex-C can interfere with the action of other drugs/medicines:
- Live vaccines (Mumps, Measles, etc.)
Gamunex C Vs Other Immune Globulins
Gammagard and Gammaplex Vs Gamunex-C
Gammagard and Gammaplex are competitors of Gamunex-C.
Gamunex-C Vs Privigen
Gamunex and Privigen, both are identified as effective intravenous immunoglobulin replacement therapies for the management of primary humoral immunodeficiencies.
Gamunex Vs IVIG-SD
As per a randomized double-blinded trial, Gamunex-C was found to be superior as compared to the IVIG-SD therapy. The adverse reactions were similar, however, Gamunex-C significantly improved acute sinusitis and bronchiectasis in primary immune deficiency patients.
Gamunex-C is a 10% immune globulin solution prepared by caprylate/chromatography. The antibody solution can be given intravenously or subcutaneously and performs superbly in conditions such as PI, CIPD, ITP, and agammaglobulinemia.
It is associated with an increased risk of thrombosis, renal failure, and hemolysis, therefore, must be used with caution.
Karim Tobgy, RPh was born and raised in Cairo, Egypt. He graduated from Cairo University in 2009 and has been a practicing pharmacist for 12 years and is certified in Sterile Products (IV) & USP (797). The most rewarding part of his job is seeing the impact of his care as a Pharmacist on the patients’ quality of life. He is currently precepting students from Marshall B. Ketchum University. In his free time, he enjoys watching documentaries and playing soccer.