Calaspargase pegol-mknl is used with other chemotherapy drugs to treat acute lymphocytic leukemia (ALL; a type of cancer of the white blood cells) in infants, children, and young adults aged 1 month to 21 years old. Calaspargase pegol-mknl is an enzyme that interferes with natural substances necessary for cancer cell growth. It works by killing or stopping the growth of cancer cells.

Calaspargase pegol-mknl comes as a solution (liquid) to be injected intravenously (into a vein) over 1 hour by a doctor or nurse in a medical office or hospital. It is usually given once every 3 weeks for as long as your doctor recommends treatment.

Your doctor may need to slow down your infusion, delay it, or stop your treatment with calaspargase pegol-mknl injection, or treat you with other medications if you experience certain side effects. Be sure to tell your doctor how you are feeling during your treatment with calaspargase pegol-mknl.

Calaspargase pegol-mknl may cause serious or life-threatening allergic reactions that are most likely to happen during the infusion or within 1 hour after the infusion. A doctor or nurse will monitor you during the infusion and for one hour after your infusion is finished to see if you are having a serious reaction to the medication. Tell your doctor or nurse immediately if you experience any of the following symptoms: swelling of the face, throat, tongue, lips, or eyes; flushing; hives; itching; rash; or difficulty swallowing or breathing.

Before receiving calaspargase pegol-mknl injection,

• tell your doctor and pharmacist if you are allergic to calaspargase pegol-mknl, pegaspargase (Oncaspar), any other medications, or any of the ingredients in calaspargase pegol-mknl injection. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have or ever had pancreatitis (swelling of the pancreas), blood clots, or severe bleeding, especially if these happened during an earlier treatment with asparaginase (Elspar), asparaginase erwinia chrysanthemi (Erwinaze) or pegaspargase (Oncaspar). Also tell your doctor if you have liver disease. Your doctor may not want you to receive calaspargase pegol-mknl.
• tell your doctor if you are pregnant or plan to become pregnant. You must take a pregnancy test before starting treatment. You should not become pregnant during your treatment with calaspargase pegol-mknl injection. You should use effective birth control to prevent pregnancy during your treatment with calaspargase pegol-mknl injection and for 3 months after your final dose. Calaspargase pegol-mknl may decrease the effectiveness of some oral contraceptives (birth control pills). You will need to use another form of birth control while receiving this medication. Talk to your doctor about other methods of birth control that will work for you. If you become pregnant while receiving calaspargase pegol-mknl injection, call your doctor immediately. Calaspargase pegol-mknl may harm the fetus.
• tell your doctor if you are breast-feeding. You should not breast-feed during your treatment with calaspargase pegol-mknl injection and for 3 months after your final dose.

Unless your doctor tells you otherwise, continue your normal diet.

Calaspargase pegol-mknl injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• diarrhea

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

• unusual or severe bleeding or bruising
• ongoing pain that begins in the stomach area, but may spread to the back
• increased thirst, frequent or increased urination
• yellowing of skin or eyes; abdominal pain; nausea; vomiting; extreme tiredness; light colored stools; dark urine
• severe headache; red, swollen, painful arm or leg; chest pain; shortness of breath
• irregular or fast heartbeat
• fever, chills, cough, or other signs of infection
• shortness of breath especially when exercising; extreme tiredness; swelling of legs, ankles, and feet; irregular or fast heartbeat

Calaspargase pegol-mknl may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to calaspargase pegol-mknl injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.