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Treatment Name: C10403 Maintenance

C10403 Maintenance is a Chemotherapy Regimen for Acute Lymphoid Leukemia (ALL)

What is C10403?
C10403 is an aggressive and complex treatment regimen for adolescents and young adults (AYA) with ALL. The C10403 regimen is similar to treatment regimens given to pediatric patients (less than 18 y.o.) and are typically more aggressive than regimens given to adults (40 years or older).

The entire C10403 chemotherapy regimen consists of 5 different treatment courses: induction, consolidation, interim maintenance, delayed intensification, and maintenance (this page).

C10403 maintenance phase (Course V) typically begins shortly after completion of the delayed intensification phase, unless white blood cell count or platelets are too low.

The Maintenance Phase of C10403 (Course V) consists of the following four medications:

  • Vincristine (Oncovin®)
  • Dexamethasone (Decadron®)
  • Methotrexate
  • 6-Mercaptopurine (6-MP)

Alternative name: 10403, CALGB 10403 maintenance (Course V)

How does C10403 work?
Each of the medications in C10403 are designed to target and kill acute lymphoblastic leukemia cells in the blood, bone marrow, or wherever else they may be.

Goals of C10403 Maintenance therapy:
C10403 maintenance is given to eliminate any remaining leukemia cells and maintain remission from the leukemia. The C10403 protocol is commonly given with the goal of cure.


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  • Vincristine intravenous (I.V.) push or I.V. infusion over 10 to 15 minutes once per month (Days 1, 29, and 57)
  • Methotrexate oral tablets by mouth once per week starting the second week of each cycle (Days 8, 15, 22, 29, 36, 43, 50, 57, 64, 71, and 78)
    • Do not take methotrexate on each Day 29 when I.T. methotrexate is given during the first four cycles of maintenance treatment
  • Dexamethasone oral tablets by mouth twice daily for five consecutive days every 4 weeks (Days 1, 2, 3, 4, 5, then Days 29, 30, 31, 32, and 33, then Days 57, 58, 59, 60, and 61)
  • 6-Mercaptopurine (6-MP) oral tablets by mouth once daily (at least one hour after evening meal) every day (Days 1 through 84 = 3 months).
    • Different amounts of tablets may need to be taken on certain days of the week. Double check the prescribed daily dose each day before taking mercaptopurine
  • Methotrexate intrathecal (I.T.) injection on Day 1 of every cycle of maintenance treatment and also on Day 29 of the first four cycles of maintenance treatment which is the first year of maintenance therapy

Estimated total infusion time for C10403 Maintenance (Course V) therapy:

  • Up to 1 hour for Days 1, 29, and 57 of each cycle
  • Infusion times are based on clinical studies, but may vary depending on doctor preference or patient tolerability. Pre-medications and intravenous (I.V.) fluids, such as hydration, may add more time

In C10403 maintenance therapy, vincristine is usually given in an outpatient infusion center, allowing the person to go home after each planned treatment. 6-Mercaptopurine, prednisone, and methotrexate are taken at home.

Each maintenance phase is repeated every 84 days (12 weeks). This is known as one Cycle. For women, each cycle is repeated to complete a total of 2 years of therapy from the start of interim maintenance therapy. For men, each cycle is repeated to complete a total of 3 years of therapy from the start of interim maintenance therapy.

NOTE: 6-Mercaptopurine (6-MP) must be filled at a retail pharmacy. Not all pharmacies carry this medicine so it is best to call ahead to ensure it is in stock before going there in person.

Click here for the common C10403 maintenance starting doses.

Side Effects

In a multi-drug regimen, each medication has unique side effects. When these medicines are given together, drug-related side effects reported in clinical studies give the best estimate of what to expect. In clinical studies, the most commonly reported serious (grade 3 or 4) side effects of C10403 maintenance are shown here:

  • Neutropenic fever (17%)
  • Infection (16%)
  • Increased blood sugar (12%)
  • Numbness or tingling in fingers or toes (9%)
  • Mouth sores (3%)
  • Fatigue (3%)
  • Increased blood triglycerides (2%)
  • Blood clot (1%)
  • Inflammation of the pancreas (1%)
  • Bleeding (1%)

On average, 1% of patients discontinue treatment due to unacceptable side effects.

Side effect videos Side Effect Videos
Neutropenic FeverNeutropenic FeverFatigue Fatigue Blood ClotsBlood ClotsBleedingBleedingNausea and VomitingNausea and VomitingDiarrheaDiarrheaAnemiaAnemia


How often is monitoring needed with C10403 Maintenance (Course V)?
Labs (blood tests) may be checked before treatment and periodically in-between treatments if needed. Labs often include: Complete Blood Count (CBC), Comprehensive Metabolic Panel (CMP), blood methotrexate levels, plus any others your doctor may order.

How often is imaging needed?
Imaging may be checked before treatment and during treatment if there is a concern for infection or medication side effect. Imaging may include: X-rays, magnetic resonance imaging (MRI), or computerized tomography (CT) scans.

How might blood test results/imaging affect treatment with C10403 Maintenance (Course V)?
Depending upon the results, your doctor may advise to continue C10403 as planned, or delay or switch therapy, or reduce the dose of specific medications due to side effects or low blood counts.

ChemoExperts Tips

  • Continuous exposure to 6-mercaptopurine (6-MP), rather than frequent stopping and restarting, has been shown to have better anti-leukemia effect. If 6-MP is causing side effects to the point where it is difficult to take, talk with your doctor to see if reducing the dose may be safe, yet still effective
  • It is usually recommend to swallow mercaptopurine tablets whole. On occasion, your doctor may have you split them in half. However, the dose of mercaptopurine per week can often be achieved by alternating the number of tablets you take each day. Your doctor or pharmacist should tell you the exact number of tablets to take on each day of the week.
  • Unless your doctor specifically tells you it is okay, you should NOT take allopurinol while taking 6-MP due to a drug interaction between these two medicines. If taken together, the allopurinol could lead to an unsafe build up of 6-MP in your body or cause the 6-MP to be less effective
  • An antiviral medication such as acyclovir or valacyclovir (Valtrex®) is usually prescribed to prevent viral infections and is taken throughout therapy, including the maintenance phase (Course V)
  • A medicine known as sulfamethoxazole/trimethoprim (more commonly called Bactrim®), is prescribed to prevent a specific type of pneumonia known as pneumocystis jiroveci pneumonia (PJP pneumonia). Because Bactrim can interact with certain medications such as methotrexate, even when methotrexate is given intrathecally, your doctor, nurse, or pharmacist will tell to hold certain doses to prevent potentially severe side effects from methotrexate
  • Omeprazole (Prilosec&®) or a similar medication may be given to prevent ulcers from dexamethasone, however it is best not to take omeprazole on the days that methotrexate is given as it could make the methotrexate more toxic
  • Patients may differ in the amount and activity of an enzyme they have that metabolizes 6-mercaptopurine, called TPMT. In some cases, genetic testing for TPMT may recommended before or during treatment with 6-mercaptopurine to test for low levels of this enzyme that could lead to increased side effects
  • Clinical outcomes may be improved by seeking treatment from a University Hospital or National Cancer Institute (NCI)-sponsored cancer center where there may be more experts with experience in treating patients with acute lymphoblastic leukemia
  • A pharmacist should ALWAYS review your medication list to ensure that drug interactions are prevented or managed appropriately
  • Clinical trials may exist for ALL. Ask your doctor if any studies are currently enrolling in your area. If not, go to to search for other centers offering study medications

Patient Assistance & Co-payment Coverage

Patients under the age of 65 years, or those with private insurance plans:
If you have insurance and are looking for patient assistance or copay assistance for C10403 Maintenance, we have provided links that may help.

Visit our Patient Assistance page and click the links to various patient assistance programs for help paying for C10403 Maintenance. Depending upon your income, they may be able to help cover the cost of:

  • Vincristine
  • 6-Mercapto­purine
  • Dexamethasone
  • Methotrexate Oral

For Branded medications (may be available for generic medications too), check with the manufacturer to determine if a co-pay card is offered and if it could reduce your monthly copay.

  • If you are uninsured, check with the manufacturer to determine if you are eligible to receive medication at no cost.

Medicare and Medicaid patients (Patients 65 years or older):
The clinic providing treatment will likely pre-authorize medications and immune therapies such as C10403 Maintenance and are the best source to help you understand drug cost.

  • Ask to speak with a patient assistance technician or financial counselor at the clinic or hospital administering this therapy.

Emotional Wellness

What is Emotional Wellness?
Emotional wellness is having a positive outlook balanced with a realistic understanding of current life events. This requires both an awareness and acceptance of your emotions. It is with this knowledge that you can develop a plan to take the necessary actions to positively impact your life.

Emotional wellness uses an ongoing process to continually reflect on the stressors of life in a constructive manner to move forward and create happiness.

Because emotional wellness is deeply connected with physical, social, and spiritual wellness, pursuing it often becomes particularly difficult in times of major illness. Despite this difficulty, working toward emotional wellness has been connected to improved treatment outcomes and a higher likelihood of achieving goals of therapy.

Learn more about pursuing emotional wellness while receiving treatment with C10403 Maintenance

Individual Drug Label Information

Vincristine (Oncovin®)

  • ​Vincristine MUST only be given by intravenous infusion. May NOT be administered any other way
  • Dosage may be reduced in patients with poor liver function
  • May interact with certain antifungal medications
  • Vincristine will cause death if administered into spinal fluid
General Vincristine (Oncovin) Side Effects
  • Nerve pain in hands or feet may increase after each dose. It is usually reversible if treatment is stopped or dose is adjusted
  • Hair loss is NOT common if vincristine is given by itself
  • May cause constipation; preventative medicines may help decrease or avoid constipation
  • Leakage into skin or surrounding muscle may cause severe irritation (extravasation)
  • Click on the vincristine (Oncovin) package insert below for reported side effects and potential drug interactions

Side Effect Videos

See DailyMed package insert.

6-Mercapto­purine (6-MP)

  • Is an oral tablet available in 50 mg
  • It is usually recommend to swallow mercaptopurine tablets whole. On occasion, your doctor may prescribe a half-tab to make a total daily dose. Ask a pharmacist before you split any tablets in half as this may not be necessary and could unnecessarily expose others to the medicine
  • Take without food, preferably at least 1 hour after evening meal. Food decreases absorption so it is best to take on an empty stomach to avoid possible decrease in effectiveness. DO NOT take with milk or citrus products
  • If you miss a dose, take the next dose as scheduled. DO NOT take two doses at once to make up for the missed dose
  • Store at room temperature and keep protected from light
  • Dosage adjustments may be required for decreased kidney or liver function
  • May interact with allopurinol. If allopurinol is used, the dose of mercaptopurine should be decreased and close monitoring should occur
  • May decrease the effects of warfarin. INR levels may need to be monitored more frequently and warfarin doses may need to be adjusted
  • May interact with olsalazine, mesalazine, or sulfasalazine causing an increased risk of side effects
  • Some patients may lack or have decreased activity in the enzyme that metabolizes mercaptopurine, known as TPMT. Genetic testing may be needed if unexpected severe side effects are experienced
  • Can cause fetal harm when given to pregnant women with the highest risk during the first trimester of pregnancy
General side effects from mercaptopurine (6-MP)
  • Commonly causes low white blood cells, red blood cells, and platelets
  • May cause liver toxicity which is often reversible when therapy with mercaptopurine is stopped
  • Can cause nausea, vomiting, and loss of appetite
  • May cause diarrhea
  • Skin rash or increased skin pigmentation can occur
  • Click on the mercaptopurine (6-MP) package insert below for reported side effects and possible drug interactions

Side Effect Videos
Nausea and VomitingNausea and VomitingDiarrheaDiarrheaFatigue Fatigue BleedingBleedingPainPainAnemiaAnemiaNeutropenic FeverNeutropenic Fever

See DailyMed package insert.

Dexamethasone (Decadron®)

  • Dexamethasone is supplied as an oral tablet or oral liquid
  • Dexamethasone may increase the risk of infection. Depending upon how much dexamethasone is taken, antibiotics may be prescribed to help prevent infection
  • Should be taken with food and with a large glass of water to avoid stomach irritation or ulcers
  • Should be taken before 6 p.m. when possible, to avoid trouble falling asleep
  • May decrease the response to vaccines; vaccines may need to be repeated at a later date to obtain maximal response
  • If taken daily for several days or weeks, the dose of dexamethasone may need to be gradually decreased (tapered) to avoid withdrawal symptoms
  • If you miss a dose, take the next dose as soon as possible
  • Should be stored at room temperature
General Dexamethasone (Decadron) Side Effects
  • May cause high blood sugar, weight gain, irritability, high blood pressure, difficulty sleeping, stomach ulcers, bone loss, muscle weakness
  • Click on the dexamethasone (Decadron) package insert below for reported side effects and potential drug Interactions
See DailyMed package insert.

Methotrexate Oral (Trexall®)

  • ​Is an oral tablet available in 2.5 mg
  • Methotrexate has the following FDA Black-Box Warnings. The risk of experiencing these side effects is much higher if methotrexate is not cleared from the body appropriately:
  1. Low red blood cells, white blood cells, and platelets
  2. Kidney injury
  3. Liver injury
  4. Severe diarrhea
  5. Mouth ulcers
  6. Stomach ulcers
  • Can be taken with or without food. Swallow tablets whole and do not chew or crush
  • If you miss a dose, call your doctor to see if you should make up the dose or not
  • Should be stored at 68° to 77° F
  • Dosage adjustments may be required for poor kidney function or poor liver function
  • May interact with non-steroidal inflammatory drugs (NSAIDs), aspirin, proton-pump inhibitors, phenytoin, and sulfa or penicillin antibiotics. These drugs should NOT be used the day before or the day of therapy with methotrexate. 
  • Ask your doctor or pharmacist to review your medications prior to receiving methotrexate 
  • Is harmful to the fetus during pregnancy. If you are of childbearing age, use multiple forms of birth control 
General side effects from methotrexate
  • Low red blood cells, white blood cells, and platelets
  • Liver injury
  • Kidney injury
  • Lung injury
  • Skin rash
  • Mouth sores
  • Nausea and vomiting
  • Diarrhea
  • Fatigue
  • Click on the methotrexate package insert below for reported side effects and possible drug interactions 

Side Effect Videos
Nausea and VomitingNausea and VomitingDiarrheaDiarrheaFatigue Fatigue AnemiaAnemia

See DailyMed package insert.

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1) Curran E and Stock W. How I treat acute lymphoblastic leukemia in older adolescents and young adults. Blood 2015;125:3702-3710.

2) Stock W, Luger SM, Advani AS, et al. A pediatric regimen for older adolescents and young adults with acute lymphoblastic leukemia: results of CALGB 10403. Blood. 2019;133:1548-1559.

Created: December 6, 2019 Updated: December 6, 2019

What is Acute Lymphoid Leukemia (ALL)?

Acute Lymphoid Leukemia (ALL), also known as acute lymphoblastic leukemia, is a disease of the lymphoid cells found in the bone marrow. Lymphoid cells are responsible for developing into cells of the immune system called B-cells, T-cells, or Natural Killer cells. In ALL, immature lymphoid cells know as "blasts" replicate at a very fast rate. Sometimes blasts crowd out the normal cells in the bone marrow so that red blood cells or platelets are unable to develop.

Common symptoms of ALL include fatigue, infection, and bruising or bleeding. ALL is the most common cancer diagnosed in children, but is rare in adults. Most cases of ALL are considered "de novo" meaning that the cause is unknown; however, some cases can be linked to certain genetic syndromes. There is no staging system for ALL. Chromosomes are often analyzed to determine which mutations in the chromosomes exist. The effectiveness of the treatment may depend upon the specific chromosome mutations that are present.

NOTE: Treatment Options listed below are not all-inclusive. Other treatments may be available. ChemoExperts provides drug information and does not recommend any one treatment over another. Only your Doctor can choose your therapy.

Common C10403 maintenance starting doses

  • Vincristine 1.5 mg/m2 (maximum 2 mg) intravenous (I.V.) push or I.V. infusion over 10 to 15 minutes on Days 1, 29, and 57
  • Oral Methotrexate 20 mg/m2 given as tablets by mouth once daily on Days 8, 15, 22, 29, 36, 43, 50, 57, 64, 71, and 78
    • Do not take methotrexate on Day 29 of the first four cycles of maintenance treatment
  • Intrathecal (IT) Methotrexate 15 mg injection on Day 1 of every cycle of maintenance treatment and also on Day 29 of the first four cycles of maintenance treatment
  • Dexamethasone 3 mg/m2 by mouth twice daily (total daily dose = 6 mg/m2) on Days 1, 2, 3, 4, and 5, then Days 29, 30, 31, 32, and 33, then Days 57, 58, 59, 60, and 61
  • 6-Mercaptopurine 75 mg/m2 oral tablets by mouth once daily (at least one hour after evening meal) on Days 1 through 84 (= 3 months)

Note: Individual doses may vary based upon your Doctor's recommendation, or drug availability.

What are adolescents and young adults (AYAs)?

The age range for this population is generally considered to be those between 18 - 39 years old, although this age range may vary slightly.

What does Cure mean?

The word “cure” means there are no cancer cells left in the body and cancer will never come back. Depending on the cancer type and stage, this may be the true goal of therapy. However, it is very difficult to prove all cancer cells are gone. Even though images, like X-rays and MRI’s, and blood tests may not show any signs of cancer, there can be a small amount of cancer cells still left in the body. Because of this, the word “remission” is used more often. This means there are no signs or symptoms of cancer. Patients in remission are followed closely for any signs of cancer returning. Sometimes, more chemotherapy may be given while in remission to prevent the cancer from coming back.

Doctors usually do not consider a patient “cured” until the chance of cancer returning is extremely low. If cancer does return, it usually happens within 5 years of having a remission. Because of this, doctors do not consider a patient cured unless the cancer has not come back within 5 years of remission. The five-year cutoff does not apply to all cancers.

What is Intrathecal (I.T.) therapy?

Intrathecal (I.T.) injection is a procedure where a needle is inserted into the spinal canal of the lower back to access the space that contains the cerebral spinal fluid (CSF). Typically, once the needle is inserted, a small amount of CSF is taken out and chemotherapy is then injected into the CSF. This is most often performed to treat cancer that is present in the CSF or to prevent cancer from invading the CSF. It is important that patients lie flat for 30 min - 1 hour after receiving an I.T. injection.

What is a CBC?

A Complete Blood Count (CBC) is a frequently ordered blood test that tells clinicians the status of your: 1) White blood cell count, 2) Hemoglobin, and 3) Platelet count at the time the test was taken.

Common uses:
1) White blood cell count (WBC): is used to determine infection risk, or response to chemotherapy. Certain chemotherapy agents may harm our good infection-fighting cells. Sometimes chemotherapy may need to be delayed to allow these cells to recover.

2) Hemoglobin: is used to determine if someone is anemic. Anytime the hemoglobin is below 12 g/dL, the person is said to be anemic. Red blood cell transfusions, and sometimes iron can be given to restore the hemoglobin level, but anemia treatment should always aim at treating the underlying cause or condition.

3) Platelet count: is used to determine if the risk of bleeding is increased or if a platelet transfusion is required to prevent bleeding. Certain medications that increase bleeding risk, such as: aspirin, certain chemotherapy agents, and blood thinners, may need to be stopped temporarily until the platelet count is within a safe range.

What is a CMP?

A Comprehensive Metabolic Panel (CMP) is a frequently ordered blood test that tells clinicians the status of your: 1) Electrolytes & Acid/Base status2) Kidney function, 3) Liver function, 4) Blood sugar, and 5) Calcium at the time the test was taken. It is commonly used to monitor liver and kidney function when beginning new medications such as chemotherapy. A total of 14 tests are run simultaneously and are shown below.

Electrolytes & Acid/Base status:
1) Sodium, 2) Potassium, 3) Carbon dioxide, 4) Chloride

Kidney Function:
5) BUN (blood urea nitrogen), 6) Serum creatinine (Scr)

Liver Function:
7) AST, 8) ALT, 9) Total bilirubin, 10) Alk Phos, 11) Albumin, 12) Total protein

Blood sugar:
13) Serum glucose

14) Serum calcium