Asparaginase in the Fight Against Acute Lymphoblastic Leukemia

Overview

A unique enzyme known as Asparaginase aids in the breakdown of L-asparagine, a form of amino acid, into less complex compounds like ammonia and l-aspartic acid. Certain bacteria, such as Escherichia coli and Erwinia chrysanthemi, are the source of this enzyme. Asparagine, an amino acid, is taken orally to cancer patients, which prevents the cancer cells from producing proteins. The United States Food and Drug Administration (USFDA) approved the Asparaginase in 1978.

Drug Group:

Asparaginase is an antineoplastic (anticancer) medication used to treat acute lymphoblastic leukemia.

Indications:

Asparaginase is used in combination with other medications to treat acute lymphoblastic leukemia (ALL), a type of malignancy.

Contraindications:

• Severe adverse reactions to other medications containing Escherichia coli (E. coli) germs, such as Asparaginase.

• Severe blood coagulation issues related to previous L-asparaginase treatment.

• Pancreatitis (pancreas inflammation) following previous administration of L-asparaginase treatment.

• Severe bleeding episodes after receiving earlier L-asparaginase treatment.

Dosage Forms and Available Strengths

Asparaginase is supplied in single-use vials with 10,000 International Units of lyophilized powder.

For Patients

What Is Acute Lymphoblastic Leukemia?

White blood cells are affected by acute lymphoblastic leukemia (ALL), a type of malignancy that originates in the bone marrow and blood. It is the most prevalent cancer among children. It occurs when the DNA of a certain type of bone marrow cell becomes distorted. Swollen lymph nodes, bruising, fever, bone pain, bleeding gums, and frequent illness are all indicators of ALL. Chemotherapy and tailored medications designed to destroy cancer cells are two possible treatment options.

What Are the Clinical Uses of Asparaginase?

Asparaginase is a medication used in combination with other medications to treat acute lymphocytic leukemia (ALL), a particular type of leukemia (blood cancer). One kind of cancer that affects white blood cells is leukemia. Asparaginase is a kind of enzyme inhibitor that inhibits the natural growth-promoting factors that cancer cells require. Doing so either stops the cancer cells from developing or kills them.

How Should Asparaginase Be Used?

Asparaginase is a medication that is often supplied in powder form. It is diluted with fluid and injected into a muscle or injected straight into a vein in the body by a physician or nurse. This procedure is performed in a hospital clinic or a doctor's office, and it typically takes thirty minutes. This medication is usually given to patients three times a week.

What Are the Side Effects of Asparaginase?

Asparaginase may cause adverse reactions. If the person feels that any of these symptoms are hurting them, let the doctor know:

• Feeling lightheaded.

• Headache.

• Trembling from the cold.

• Decrease in weight.

• Vomiting.

• Being feverish.

• Feeling sick.

• Not experiencing hunger.

• Exhausted.

Certain adverse effects may be dangerous. Make a quick call to the physician if the person has:

• Breathing difficulties.

• Swelling in face, arms, or legs.

• Seizures (an uncontrollable increase in electrical activity that occurs between brain cells).

• A yellowing of the skin or eyes.

• Severe backache radiating from the abdomen.

• Perceiving or hearing unreal events.

• Pain in the chest.

• Frequent urination.

• Feeling very thirsty.

• Feeling confused.

• A sore spot on the upper right stomach.

• Dark urine.

There may be other adverse effects from Asparaginase. If the person has any odd side effects while taking this medication, they should contact the doctor.

What Are the Things to Inform the Doctor Before Taking Asparaginase?

Prior to beginning asparaginase therapy, it is critical to:

• Inform the physician and pharmacist of allergies to Asparaginase or related medications.

• Let the doctor know about all the medications the patient takes at the moment, including over-the-counter, prescription, vitamin, and herbal items.

• Let the doctor know if the person has ever experienced serious bleeding, blood clots, or pancreatitis, especially while receiving Asparaginase treatment in the past. In such circumstances, the physician may advise against taking Asparaginase.

• They should talk to the doctor if they are breastfeeding, intend to become pregnant, or are already pregnant. They should get in touch with their doctor right away if they become pregnant while taking Asparaginase.

Dietary Consideration: Maintain the same diet unless advised otherwise by the doctor.

Missed Dose: It is critical to take this medication exactly as prescribed each time. Consult the pharmacist or doctor as soon as possible to get a revised dosage schedule if one misses a dose.

Overdose: It is critical to get in touch with a poison control center right away if someone overdoses and exhibits serious symptoms like breathing difficulties or fainting.

For Doctors

Pharmacodynamics:

Researchers examined the association between the amounts of Asparagine in the body and the activity of native Asparaginase in individuals with untreated, standard-risk acute lymphoblastic leukemia (ALL) who received the enzyme. They discovered that there was a considerable decline in asparagine levels in the blood when the enzyme activity was greater than 0.1 international units per milliliter. Asparagine levels in the blood were 41 micromoles per liter (µM) on average prior to treatment; following treatment, these levels dropped to less than three µM.

Asparagine levels in the cerebrospinal fluid, which surrounds the brain and spinal cord, also decreased in the patients' fluid from these investigations. The average level was 2.8 µM prior to treatment, but by day seven, it had declined to 1.0 µM, and by day 28, it had even further decreased to 0.3 µM.

Mechanism of Action:

Asparaginase functions by selectively destroying leukemia cells. It accomplishes this by drawing asparagine out of the blood. Leukemia cells that cannot produce asparagine on their own require it to survive. They are dependent on other sources for information. These leukemia cells are unable to survive and eventually die off when Asparaginase eliminates asparagine from the blood. Since normal cells are able to produce asparagine on their own, they are less impacted. Therefore, the asparagine being removed from the blood does not harm them as much.

Pharmacokinetics:

Daily venous injections of L-asparaginase led to a gradual rise in the drug's levels in the blood in research involving patients with leukemia and advanced cancer. It took from eight to 30 hours for the medication level in the blood to drop by half. The apparent volume of distribution, or the amount of space in the body where the medication can spread, was marginally greater than the volume of plasma in the circulation. Asparaginase levels in the fluid around the brain and spinal cord, however, were incredibly low, less than one percent of what was detected in the blood.

The maximum concentrations of the medication in the blood were obtained between 14 and 24 hours following the injection of L-asparaginase into the muscles of trial participants. The duration required for the medication concentrations in the blood to decrease by 50 percent varied between 34 and 49 hours.

What Is the Prescribed Dosage and Method of Administration For Asparaginase?

• Recommended Dosage: The recommended dosage for the drug Asparaginase is 6,000 international units per square meter of body area. This is usually given three times a week through intravenous injection (into a vein) or intramuscular injection (into the muscle).

• Guidelines for Administration: Asparaginase should only be injected into the muscle in amounts no more than two milliliters at a time. If a bigger volume is needed, it needs to be split between two injection sites. It is best to throw away any leftovers. When injected intravenously, Asparaginase needs to be diluted with either a five percent Dextrose Injection (D5W) or sodium chloride injection and infused slowly over a minimum of 30 minutes. Remember to throw away any piece that has not been used.

• Setting up and Managing Precautions:

  • Fill the 10,000-unit vial with two milliliters of sodium chloride injection to reconstitute Elspar for intramuscular delivery. Using a sterile syringe, withdraw the necessary amount of reconstituted Asparaginase (5,000 international units per milliliter).

  • Reconstitute Elspar for intravenous delivery by filling the 10,000 unit vial with five milliliters of sterile water for injection or sodium chloride injection. Using a sterile syringe, withdraw the necessary amount of reconstituted Asparaginase (2,000 international units per milliliter).

  • Utilizing the reconstitution of Asparaginase within eight hours of preparation is crucial.

  • Visually check the solution for any discoloration, cloudiness, or particle debris prior to administration. Should any of these be found, the solution ought to be thrown away. Nevertheless, over time, a very small number of particles that resemble gelatinous fibers may occasionally form. Without compromising the medication's potency, they can be eliminated during delivery by filtering through a 5.0-micron filter.

Storage and Handling: Asparaginase vials should be kept in the refrigerator between two and eight degrees Celsius (36 and 46 degrees Fahrenheit). There are no preservatives in the solution after it is combined with liquid. Any leftover combined solution should be stored in the refrigerator at the same temperature and thrown out after eight hours or if it starts to get hazy.

Clinical Studies: In research, Asparaginase was given to 823 children under the age of 16 who had recently been diagnosed with acute lymphoblastic or acute undifferentiated leukemia in addition to other chemotherapy medications to aid in their recovery. Asparaginase was injected into the muscle three times a week for a total of nine shots.

758 (about 93 percent) of the 815 patients that were assessed had complete remission, meaning their cancer had completely disappeared. In a prior trial, 429 out of 499 patients (or around 86 percent) who got the same chemotherapeutic medications but not Asparaginase, experienced total remission. This implies that the number of patients who experienced recovery increased when Asparaginase was added to the treatment.

Drug Interactions:

Asparaginase and other medications have not been the subject of any official drug interaction research.

Nonclinical Toxicology:

• Carcinogenesis, Mutagenesis, and Fertility Impairment: There has not been any extensive research done to look into the possibility that the drug Asparaginase can cause cancer in animals. In the same way, no relevant study has looked into its ability to cause genetic abnormalities. Asparaginase, however, did not show any tendency to produce mutations in the Ames assay, a particular laboratory test used to assess mutagenic effects. Moreover, not much research has been done to determine whether Asparaginase influences an animal's ability to conceive. Overall, not much is known about Asparaginase’s ability to cause cancer, mutate genetic defects, or affect an animal's ability to conceive.

• Animal Toxicology: High doses of Asparaginase were given to rabbits in animal studies, and the results showed tissue death and enlargement in several areas of the pancreas. Interestingly, rabbits receiving smaller dosages of Asparaginase did not experience these effects. The amounts given to the rabbits were notably more than the typical dosages advised for human consumption. Importantly, although side effects were seen in rabbits' pancreas at large dosages, they did not correspond with pancreatitis, a particular disease characterized by inflammation of the pancreas.

Warnings and Precautions:

• Allergic Reaction: When receiving Asparaginase, patients may experience severe allergic reactions. Having previously used Asparaginase or other comparable medications increases the risk. After administering Asparaginase, stay with patients for an hour in a location where they can easily seek medical attention if necessary, such as a hospital. Stop giving Asparaginase if the person gets a severe allergic reaction.

• Blood Clots: Asparaginase may occasionally cause severe blood clotting issues, especially those involving the brain. If this happens, stop giving Asparaginase.

• Pancreatitis: Elspar may occasionally result in pancreatitis, an inflammation of the pancreas. If pancreatitis is suspected, stop taking Asparaginase and keep an eye out for any abdominal pain.

• Glucose Intolerance: Asparaginase use may cause glucose intolerance in certain people. Regularly check the blood sugar levels.

• Coagulopathy: Asparaginase may have an impact on blood coagulation, resulting in low fibrinogen levels, an extended prothrombin time, and a partial thromboplastin time. Track blood clotting indicators and adjust treatment as necessary.

• Liver Issues: Elevated bilirubin and liver enzyme values are indicators of potential liver damage caused by Asparaginase. Assess liver health both before and after treatment.

• Neurological Problems: Asparaginase may result in posterior reversible encephalopathy syndrome (PRES), a neurological condition when administered with other medications. Headaches, convulsions, and mental status changes are among the symptoms. Cut off Asparaginase and treat symptoms as soon as suspected.

• Medication Errors: Asparaginase mistakes have been made in the past, particularly when they are confused with other comparable medications. Prior to administering medication to a patient, always double-check it. Without appropriate supervision, do not substitute Asparaginase with other medications such as pegylated E. coli asparaginase or Erwinia asparaginase.

Use in Specific Populations:

• Pregnancy: Asparaginase may pose dangers to expectant mothers as it is classified as pregnancy category C. High doses of Asparaginase produced issues with weight gain in mothers and their offspring, according to studies conducted on mice and rats. Additionally, it results in aberrant development in babies. Lower amounts administered to pregnant rabbits resulted in malformations and damage to the developing embryos. To be certain of Asparaginase’s safety during pregnancy, there has not been enough research done on expectant mothers. Pregnant women should only be prescribed it by doctors if the advantages clearly exceed the hazards.

• Nursing Mothers: Asparaginase’s ability to enter human breast milk is unknown. Given how vital the medication is for the mother, mothers should discuss with their doctors whether to cease breastfeeding or stop using Asparaginase, as many pharmaceuticals have the potential to create major issues for nursing newborns.

• Use in Children and Older People: As not enough research has been done on older persons or children, there is not enough information available concerning how Asparaginase impacts these age groups.