2.2 Colorectal Single Agent Regimens 1 and 2
Administer irinotecan hydrochloride injection as a 90-minute intravenous infusion. The currently recommended regimens are shown in Table 3.
A reduction in the starting dose by one dose level of irinotecan hydrochloride injection may be considered for patients with any of the following conditions: prior pelvic/abdominal radiotherapy, performance status of 2, or increased bilirubin levels. Dosing for patients with bilirubin > 2 mg/dL cannot be recommended because there is insufficient information to recommend a dose in these patients.
Table 3. Single-Agent Regimens of Irinotecan Hydrochloride Injection and Dose Modifications
a Subsequent doses may be adjusted as high as 150 mg/m2 or to as low as 50 mg/m2 in 25 to 50 mg/m2 decrements depending upon individual patient tolerance.
b Subsequent doses may be adjusted as low as 200 mg/m2 in 50 mg/m2 decrements depending upon individual patient tolerance.
c Provided intolerable toxicity does not develop, treatment with additional cycles may be continued indefinitely as long as patients continue to experience clinical benefit.
Regimen 1 (weekly)a
125 mg/m2 intravenous infusion over 90 minutes, days 1,8,15,22 then 2-week rest
Starting Dose and Modified Dose Levelsc (mg/m2)
Starting Dose
Dose Level -1
Dose Level -2
125
100
75
Regimen 2 (every 3 weeks)b
350 mg/m2 intravenous infusion over 90 minutes, once every 3 weeksc
Starting Dose and Modified Dose Levels (mg/m2)
Starting Dose
Dose Level -1
Dose Level -2
350
300
250
Dose Modifications
Based on recommended dose-levels described in Table 3, Single-Agent Regimens of Irinotecan Hydrochloride Injection and Dose Modifications, subsequent doses should be adjusted as suggested in Table 4, Recommended Dose Modifications for Single-Agent Schedules. All dose modifications should be based on the worst preceding toxicity.
Table 4: Recommended Dose Modifications for Single-Agent Schedulesa
a All dose modifications should be based on the worst preceding toxicity
b National Cancer Institute Common Toxicity Criteria (version 1.0)
c Pretreatment
d Excludes alopecia, anorexia, asthenia
A new cycle of therapy should not begin until the granulocyte count has recovered to ≥ 1500/mm3, and the platelet count has recovered to ≥ 100,000/mm3, and treatment-related diarrhea is fully resolved. Treatment should be delayed 1 to 2 weeks to allow for recovery from treatment-related toxicities. If the patient has not recovered after a 2-week delay, consideration should be given to discontinuing irinotecan hydrochloride injection.
Worst Toxicity NCI Gradeb (Value)
During a Cycle of Therapy
At the Start of the Next Cycles of Therapy (After Adequate Recovery), Compared with the Starting Dose in the Previous Cyclea
Weekly
Weekly
Once Every 3 Weeks
No toxicity
Maintain dose level
↑ 25 mg/m2 up to a maximum dose of 150 mg/m2
Maintain dose level
Neutropenia
1 (1500 to
1999/mm3)
Maintain dose level
Maintain dose level
Maintain dose level
2 (1000 to
1499/mm3)
↓ 25 mg/m2
Maintain dose level
Maintain dose level
3 (500 to 999/mm3)
Omit dose until resolved to ≤ grade 2, then ↓ 25 mg/m2
↓ 25 mg/m2
↓ 50 mg/m2
4 (< 500/mm3)
Omit dose until resolved to ≤ grade 2, then ↓ 50 mg/m2
↓ 50 mg/m2
↓ 50 mg/m2
Neutropenic fever
Omit dose until resolved, then ↓ 50 mg/m2 when resolved
↓ 50 mg/m2
↓ 50 mg/m2
Other hematologic toxicities
Dose modifications for leukopenia, thrombocytopenia, and anemia during a cycle of therapy and at the start of subsequent cycles of therapy are also based on NCI toxicity criteria and are the same as recommended for neutropenia above.
Diarrhea
1 (2 to 3 stools/day > pretxc)
Maintain dose level
Maintain dose level
Maintain dose level
2 (4 to 6 stools/day > pretx)
↓ 25 mg/m2
Maintain dose level
Maintain dose level
3 (7 to 9 stools/day > pretx)
Omit dose until resolved to ≤ grade 2, then ↓ 25 mg/m2
↓ 25 mg/m2
↓ 50 mg/m2
4 (≥ 10 stools/day > pretx)
Omit dose until resolved to ≤ grade 2 then ↓ 50 mg/m2
↓ 50 mg/m2
↓ 50 mg/m2
Other nonhematologicd toxicities
1
Maintain dose level
Maintain dose level
Maintain dose level
2
↓ 25 mg/m2
↓ 25 mg/m2
↓ 50 mg/m2
3
Omit dose until resolved to ≤ grade 2, then ↓ 25 mg/m2
↓ 25 mg/m2
↓ 50 mg/m2
4
Omit dose until resolved to ≤ grade 2, then ↓ 50 mg/m2
↓ 50 mg/m2
↓ 50 mg/m2
2.3 Dosage in Patients with Reduced UGT1A1 Activity
When administered in as a single-agent, a reduction in the starting dose by at least one level of irinotecan hydrochloride injection should be considered for patients known to be homozygous for the UGT1A1*28 allele [see Dosage and Administration (2.2) and Warnings and Precautions (5.3)]. However, the precise dose reduction in this patient population is not known, and subsequent dose modifications should be considered based on individual patient tolerance to treatment (see Tables 1 to 4).
2.4 Premedication
It is recommended that patients receive premedication with antiemetic agents. In clinical studies of the weekly dosage schedule, the majority of patients received 10 mg of dexamethasone given in conjunction with another type of antiemetic agent, such as a 5-HT3 blocker (e.g., ondansetron or granisetron). Antiemetic agents should be given on the day of treatment, starting at least 30 minutes before administration of irinotecan hydrochloride injection. Physicians should also consider providing patients with an antiemetic regimen (e.g., prochlorperazine) for subsequent use as needed.
Prophylactic or therapeutic administration of atropine should be considered in patients experiencing cholinergic symptoms.
2.5 Preparation of Infusion Solution
Inspect vial contents for particulate matter and discoloration and repeat inspection when drug product is withdrawn from vial into syringe.
Irinotecan hydrochloride injection 20 mg/mL is intended for single use only and any unused portion should be discarded.
Irinotecan hydrochloride injection must be diluted prior to infusion. Irinotecan hydrochloride injection should be diluted in 5% Dextrose Injection, USP, (preferred) or 0.9% Sodium Chloride Injection, USP, to a final concentration range of 0.12 mg/mL to 2.8 mg/mL. Other drugs should not be added to the infusion solution.
The solution is physically and chemically stable for up to 24 hours at room temperature and in ambient fluorescent lighting. Solutions diluted in 5% Dextrose Injection, USP, and stored at refrigerated temperatures (approximately 2° to 8°C, 36° to 46°F), and protected from light are physically and chemically stable for 48 hours. Refrigeration of admixtures using 0.9% Sodium Chloride Injection, USP, is not recommended due to a low and sporadic incidence of visible particulates. Freezing irinotecan hydrochloride injection and admixtures of irinotecan hydrochloride injection may result in precipitation of the drug and should be avoided.
The irinotecan hydrochloride injection solution should be used immediately after reconstitution as it contains no antibacterial preservative. Because of possible microbial contamination during dilution, it is advisable to use the admixture prepared with 5% Dextrose Injection, USP, within 24 hours if refrigerated (2° to 8°C, 36° to 46°F). In the case of admixtures prepared with 5% Dextrose Injection, USP, or Sodium Chloride Injection, USP, the solutions should be used within 4 hours if kept at room temperature. If reconstitution and dilution are performed under strict aseptic conditions (e.g., on Laminar Air Flow bench), irinotecan hydrochloride injection solution should be used (infusion completed) within 12 hours at room temperature or 24 hours if refrigerated (2° to 8°C, 36° to 46°F).
2.6 Safe Handling
Care should be exercised in the handling and preparation of infusion solutions prepared from irinotecan hydrochloride injection. The use of gloves is recommended. If a solution of irinotecan hydrochloride injection contacts the skin, wash the skin immediately and thoroughly with soap and water. If irinotecan hydrochloride injection contacts the mucous membranes, flush thoroughly with water. Several published guidelines for handling and disposal of anticancer agents are available.
2.7 Extravasation
Care should be taken to avoid extravasation, and the infusion site should be monitored for signs of inflammation. Should extravasation occur, flushing the site with sterile water and applications of ice are recommended.