Pemetrexed disodium heptahydrate has the chemical name L-Glutamine acid, N-[4-[2-(2-amino-4,7-dihydro-4-oxo1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-,disodium salt, heptahydrate. It is a white to almost-white solid with a molecular formula of C20H19N5Na2O67H2O and a molecular weight of 597.49. The Structural formula is as follows:
ZINOTECANis a pale yellow to yellow crystalline powder, with the empirical formula C33H38N4O6•HCl•3H2O and a molecular weight of 677.19. It is slightly soluble in water and organic solvents.
Generic Name : Irinotecan injections
Each ml contains:
Irinotecan Trihydrate …………….20mg
Excipients …………………………………………………………q.s.
Irinotecan is a derivative of camptothecin. Camptothecins interact specifically with the enzyme topoisomerase I which relieves torsional strain in DNA by inducing reversible single-strand breaks. Irinotecan and its active metabolite SN-38 bind to the topoisomerase I-DNA complex and prevent religation of these single-strand breaks. Current research suggests that the cytotoxicity of irinotecan is due to double-strand DNA damage produced during DNA synthesis when replication enzymes interact with the ternary complex formed by topoisomerase I, DNA, and either irinotecan or SN-38. Mammalian cells cannot efficiently repair these double-strand breaks.
Irinotecan serves as a water-soluble precursor of the lipophilic metabolite SN-38. SN38 is formed from irinotecan by carboxylesterase-mediated cleavage of the carbamate bond between the camptothecin moiety and the dipiperidino side chain. SN-38 is approximately 1000 times as potent as irinotecan as an inhibitor of topoisomerase I purified from human and rodent tumor cell lines. In vitro cytotoxicity assays show that the potency of SN-38 relative to irinotecan varies from 2- to 2000-fold. However, the plasma area under the concentration versus time curve (AUC) values for SN-38 are 2% to 8% of irinotecan and SN-38 is 95% bound to plasma proteins compared to approximately 50% bound to plasma proteins for irinotecan (see Pharmacokinetics). The precise contribution of SN-38 to the activity of ZINOTECANis thus unknown. Both irinotecan and SN-38 exist in an active lactone form and an inactive hydroxy acid anion form. A pH-dependent equilibrium exists between the two forms such that an acid pH promotes the formation of the lactone, while a more basic pH favors the hydroxy acid anion form.
Administration of irinotecan has resulted in antitumor activity in mice bearing cancers of rodent origin and in human carcinoma xenografts of various histological types.
After intravenous infusion of irinotecan in humans, irinotecan plasma concentrations decline in a multiexponential manner, with a mean terminal elimination half-life of about 6 to 12 hours. The mean terminal elimination half-life of the active metabolite SN-38 is about 10 to 20 hours. The half-lives of the lactone (active) forms of irinotecan and SN-38 are similar to those of total irinotecan and SN-38, as the lactone and hydroxy acid forms are in equilibrium.
ZINOTECAN Injection is indicated as a component of first-line therapy in combination with 5-fluorouracil and leucovorin for patients with metastatic carcinoma of the colon or rectum. Irinotecan is also indicated for patients with metastatic carcinoma of the colon or rectum whose disease has recurred or progressed following initial fluorouracil-based therapy.
Patients should be carefully monitored for toxicity and doses of Irinotecan should be modified as necessary to accommodate individual patient tolerance to treatment. Recommended Dose Modifications for Single-Agent Schedules. All dose modifications should be based on the worst preceding toxicity.
A new cycle of therapy should not begin until the toxicity has recovered to NCI grade 1 or less. Treatment may be delayed 1 to 2 weeks to allow for recovery from treatment- related toxicity. If the patient has not recovered, consideration should be given to discontinuing this combination therapy. Provided intolerable toxicity does not develop, treatment with additional cycles of Irinotecan may be continued indefinitely as long as patients continue to experience clinical benefit.
Dosage in Patients with Reduced UGT1A1 Activity
When administered in combination with other agents, or as a single-agent, a reduction in the starting dose by at least one level of Irinotecan should be considered for patients known to be homozygous for the UGT1A1*28 allele (seeCLINICAL PHARMACOLOGYandWARNINGS). 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.
Preparation & Administration Precautions
As with other potentially toxic anticancer agents, care should be exercised in the handling and preparation of infusion solutions prepared from ZINOTECAN Injection. The use of gloves is recommended. If a solution of Irinotecan contacts the skin, wash the skin immediately and thoroughly with soap and water. If Irinotecan contacts the mucous membranes, flush thoroughly with water. Several published guidelines for handling and disposal of anticancer agents are available.1-7
- General :Outside of a well-designed clinical study, ZINOTECAN Injection should not be used in combination with the “Mayo Clinic” regimen of 5-FU/LV (administration for 4-5 consecutive days every 4 weeks) because of reports of increased toxicity, including toxic deaths. Irinotecan should be used as recommended (seeIn patients receiving either Irinotecan/5-FU/LV or 5-FU/LV in the clinical trials, higher rates of hospitalization, neutropenic fever, thromboembolism, first-cycle treatment discontinuation, and early deaths were observed in patients with a baseline performance status of 2 than in patients with a baseline performance status of 0 or 1.Diarrhea :Irinotecan can induce both early and late forms of diarrhea that appear to be mediated by different mechanisms. Early diarrhea (occurring during or shortly after infusion of Irinotecan) is cholinergic in nature. It is usually transient and only infrequently is severe. It may be accompanied by symptoms of rhinitis, increased salivation, meiosis, lacrimation, diaphoresis, flushing, and intestinal hyperperistalsis that can cause abdominal cramping. Early diarrhea and other cholinergic symptoms may be prevented or ameliorated by administration of atropine (see PRECAUTIONS, GENERAL, for dosing recommendations for atropine).Late diarrhea (generally occurring more than 24 hours after administration of Irinotecan) can be life threatening since it may be prolonged and may lead to dehydration, electrolyte imbalance, or sepsis. Late diarrhea should be treated promptly with loperamide (see PRECAUTIONS, INFORMATION FOR PATIENTS, for dosing recommendations for loperamide). Patients with diarrhea should be carefully monitored, should be given fluid and electrolyte replacement if they become dehydrated, and should be given antibiotic support if they develop ileus, fever, or severe neutropenia. After the first treatment, subsequent weekly chemotherapy treatments should be delayed in patients until return of pretreatment bowel function for at least 24 hours without need for anti-diarrhea medication. If grade 2, 3, or 4 late diarrhea occurs subsequent doses of Irinotecan should be decreased within the current cycle (see DOSAGE AND ADMINISTRATION).Neutropenia :Deaths due to sepsis following severe neutropenia have been reported in patients treated with Irinotecan. Neutropenic complications should be managed promptly with antibiotic support. Therapy with Irinotecan should be temporarily omitted during a cycle of therapy if neutropenic fever occurs or if the absolute neutrophil count drops <1000/mm3. After the patient recovers to an absolute neutrophil count ≥1000/mm3, subsequent doses of Irinotecan should be reduced depending upon the level of neutropenia observed (see DOSAGE AND ADMINISTRATION).
Routine administration of a colony-stimulating factor (CSF) is not necessary, but physicians may wish to consider CSF use in individual patients experiencing significant neutropenia.
Patients with Reduced UGT1A1 Activity :
Individuals who are homozygous for the UGT1A1*28 allele (UGT1A1 7/7 genotype) are at increased risk for neutropenia following initiation of Irinotecan treatment.
In a study of 66 patients who received single-agent Irinotecan (350 mg/m2 once-every-3-weeks), the incidence of grade 4 neutropenia in patients homozygous for the UGT1A1*28 allele was 50%, and in patients heterozygous for this allele (UGT1A1 6/7 genotype) the incidence was 12.5%. No grade 4 neutropenia was observed in patients homozygous for the wild-type allele (UGT1A1 6/6 genotype).
In a prospective study (n=250) to investigate the role of UGT1A1*28 polymorphism in the development of toxicity in patients treated with Irinotecan (180 mg/m2) in combination with infusional 5-FU/LV, the incidence of grade 4 neutropenia in patients homozygous for the UGT1A1*28 allele was 4.5%, and in patients heterozygous for this allele the incidence was 5.3%. Grade 4 neutropenia was observed in 1.8% of patients homozygous for the wild-type allele.
In another study in which 109 patients were treated with Irinotecan (100-125 mg/m2) in combination with bolus 5-FU/LV, the incidence of grade 4 neutropenia in patients homozygous for the UGT1A1*28 allele was 18.2%, and in patients heterozygous for this allele the incidence was 11.1%. Grade 4 neutropenia was observed in 6.8% of patients homozygous for the wild-type allele.
When administered in combination with other agents, or as a single-agent, a reduction in the starting dose by at least one level of Irinotecan should be considered for patients known to be homozygous for the UGT1A1*28 allele. 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 DOSAGE AND ADMINISTRATION and PRECAUTIONS, LABORATORY TESTS).
Hypersensitivity :
Hypersensitivity reactions including severe anaphylactic or anaphylactoid reactions have been observed.
Colitis/Ileus :
Cases of colitis complicated by ulceration, bleeding, ileus, and infection have been observed. Patients experiencing ileus should receive prompt antibiotic support (see PRECAUTIONS).
Renal Impairment/Renal Failure :
Rare cases of renal impairment and acute renal failure have been identified, usually in patients who became volume depleted from severe vomiting and/or diarrhea.
Thromboembolism :
Thromboembolic events have been observed in patients receiving irinotecan-containing regimens; the specific cause of these events has not been determined.
Pulmonary Toxicity :
Interstitial Pulmonary Disease (IPD)-like events, including fatalities, have been reported in patients receiving irinotecan (in combination and as monotherapy) for treatment of colorectal cancer and other advanced solid tumors. In the event of an acute onset of new or progressive, unexplained pulmonary symptoms such as dyspnea, cough, and fever, irinotecan and other co-prescribed chemotherapeutic agents should be interrupted pending diagnostic evaluation. If IPD is diagnosed, irinotecan and other chemotherapy should be discontinued and appropriate treatment instituted as needed (see ADVERSE REACTIONS: OVERVIEW OF ADVERSE EVENTS: RESPIRATORY).
Pregnancy :
Irinotecan may cause fetal harm when administered to a pregnant woman. Radioactivity related to 14C-irinotecan crosses the placenta of rats following intravenous administration of 10 mg/kg (which in separate studies produced an irinotecan Cmax and AUC about 3 and 0.5 times, respectively, the corresponding values in patients administered 125 mg/m2). Administration of 6 mg/kg/day intravenous irinotecan to rats (which in separate studies produced an irinotecan Cmax and AUC about 2 and 0.2 times, respectively, the corresponding values in patients administered 125 mg/m2) and rabbits (about one-half the recommended human weekly starting dose on a mg/m2 basis) during the period of organogenesis, is embryotoxic as characterized by increased post-implantation loss and decreased numbers of live fetuses. Irinotecan was teratogenic in rats at doses greater than 1.2 mg/kg/day (which in separate studies produced an irinotecan Cmax and AUC about 2/3 and 1/40th, respectively, of the corresponding values in patients administered 125 mg/m2) and in rabbits at 6.0 mg/kg/day (about one-half the recommended human weekly starting dose on a mg/m2 basis). Teratogenic effects included a variety of external, visceral, and skeletal abnormalities. Irinotecan administered to rat dams for the period following organogenesis through weaning at doses of 6 mg/kg/day caused decreased learning ability and decreased female body weights in the offspring. There are no adequate and well-controlled studies of irinotecan in pregnant women. If the drug is used during pregnancy, or if the patient becomes pregnant while receiving this drug, the patient should be apprised of the potential hazard to the fetus. Women of childbearing potential should be advised to avoid becoming pregnant while receiving treatment with Irinotecan.
- ZINOTECAN Injection is administered by intravenous infusion. 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.Premedication with Antiemetics :Irinotecan is emetigenic. 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. Physicians should also consider providing patients with an antiemetic regimen (e.g., prochlorperazine) for subsequent use as needed.Treatment of Cholinergic Symptoms :Prophylactic or therapeutic administration of 0.25 to 1 mg of intravenous or subcutaneous atropine should be considered (unless clinically contraindicated) in patients experiencing rhinitis, increased salivation, miosis, lacrimation, diaphoresis, flushing, abdominal cramping, or diarrhea (occurring during or shortly after infusion of Irinotecan). These symptoms are expected to occur more frequently with higher irinotecan doses.Immunosuppressant Effects/Increased Susceptibility to Infections :Administration of live or live-attenuated vaccines in patients immunocompromised by chemotherapeutic agents including Irinotecan, may result in serious or fatal infections. Avoid vaccination with a live vaccine in patients receiving irinotecan. Killed or inactivated vaccines may be administered; however, the response to such vaccines may be diminished.Patients at Particular Risk :
In patients receiving either irinotecan/5-FU/LV or 5-FU/LV in the clinical trials, higher rates of hospitalization, neutropenic fever, thromboembolism, first-cycle treatment discontinuation, and early deaths were observed in patients with a baseline performance status of 2 than in patients with a baseline performance status of 0 or 1. Patients who had previously received pelvic/abdominal radiation and elderly patients with comorbid conditions should be closely monitored.
The use of Irinotecan in patients with significant hepatic dysfunction has not been established. In clinical trials of either dosing schedule, irinotecan was not administered to patients with serum bilirubin >2.0 mg/dL, or transaminase >3 times the upper limit of normal if no liver metastasis, or transaminase >5 times the upper limit of normal with liver metastasis. In clinical trials of the weekly dosage schedule, patients with modestly elevated baseline serum total bilirubin levels (1.0 to 2.0 mg/dL) had a significantly greater likelihood of experiencing first-cycle, grade 3 or 4 neutropenia than those with bilirubin levels that were less than 1.0 mg/dL (50% [19/38] versus 18% [47/226]; p<0.001). (Also see CLINICAL PHARMACOLOGY: PHARMACOKINETICS IN SPECIAL POPULATIONS: Hepatic Insufficiency). Patients with deficient glucuronidation of bilirubin, such as those with Gilbert’s syndrome, may be at greater risk of myelosuppression when receiving therapy with Irinotecan.
Ketoconazole, enzyme-inducing anticonvulsants and St. John’s Wort are known to have drug-drug interactions with irinotecan therapy. (See Drug-Drug Interactions sub-section under CLINICAL PHARMACOLOGY)
Irinotecan commonly causes neutropenia, leucopenia, and anemia, any of which may be severe and therefore should not be used in patients with severe bone marrow failure. Patients must not be treated with irinotecan until resolution of the bowel obstruction. Patients with hereditary fructose intolerance should not be given Irinotecan, as this product contains sorbitol.
Information for Patients :
Patients and patients’ caregivers should be informed of the expected toxic effects of Irinotecan, particularly of its gastrointestinal complications, such as nausea, vomiting, abdominal cramping, diarrhea, and infection. Each patient should be instructed to have loperamide readily available and to begin treatment for late diarrhea (generally occurring more than 24 hours after administration of Irinotecan) at the first episode of poorly formed or loose stools or the earliest onset of bowel movements more frequent than normally expected for the patient. One dosage regimen for loperamide used in clinical trials consisted of the following (Note: This dosage regimen exceeds the usual dosage recommendations for loperamide.): 4 mg at the first onset of late diarrhea and then 2 mg every 2 hours until the patient is diarrhea-free for at least 12 hours. Loperamide is not recommended to be used for more than 48 consecutive hours at these doses, because of the risk of paralytic ileus. During the night, the patient may take 4 mg of loperamide every 4 hours. Premedication with loperamide is not recommended. The use of drugs with laxative properties should be avoided because of the potential for exacerbation of diarrhea. Patients should be advised to contact their physician to discuss any laxative use.
Patients should be instructed to contact their physician or nurse if any of the following occur: diarrhea for the first time during treatment; black or bloody stools; symptoms of dehydration such as lightheadedness, dizziness, or faintness; inability to take fluids by mouth due to nausea or vomiting; inability to get diarrhea under control within 24 hours; or fever or evidence of infection.
Patients should be warned about the potential for dizziness or visual disturbances which may occur within 24 hours following the administration of Irinotecan, and advised not to drive or operate machinery if these symptoms occur.
Patients should be alerted to the possibility of alopecia.
Laboratory Tests :
Careful monitoring of the white blood cell count with differential, hemoglobin, and platelet count is recommended before each dose of Irinotecan.
UGT1A1 Testing :
A laboratory test is available to determine the UGT1A1 status of patients. Testing can detect the UGT1A1 6/6, 6/7 and 7/7 genotypes (See WARNINGS).
First-Line Combination Therapy
A total of 955 patients with metastatic colorectal cancer received the recommended regimens of irinotecan in combination with 5-FU/LV, 5-FU/LV alone, or irinotecan alone. In the two phase 3 studies, 370 patients received irinotecan in combination with 5-FU/LV, 362 patients received 5-FU/LV alone, and 223 patients received irinotecan alone.
In Study 1, 49 (7.3%) patients died within 30 days of last study treatment: 21 (9.3%) received irinotecan in combination with 5-FU/LV, 15 (6.8%) received 5-FU/LV alone, and 13 (5.8%) received irinotecan alone. Deaths potentially related to treatment occurred in 2 (0.9%) patients who received irinotecan in combination with 5-FU/LV (2 neutropenic fever/sepsis), 3 (1.4%) patients who received 5-FU/LV alone (1 neutropenic fever/sepsis, 1 CNS bleeding during thrombocytopenia, 1 unknown) and 2 (0.9%) patients who received irinotecan alone (2 neutropenic fever). Deaths from any cause within 60 days of first study treatment were reported for 15 (6.7%) patients who received irinotecan in combination with 5-FU/LV, 16 (7.3%) patients who received 5FU/ LV alone, and 15 (6.7%) patients who received irinotecan alone. Discontinuations due to adverse events were reported for 17 (7.6%) patients who received irinotecan in combination with 5FU/LV, 14 (6.4%) patients who received 5-FU/LV alone, and 26 (11.7%) patients who received irinotecan alone.
The adverse effects of Irinotecan, such as myelosuppression and diarrhea, would be expected to be exacerbated by other antineoplastic agents having similar adverse effects.
Patients who have previously received pelvic/ abdominal irradiation are at increased risk of severe myelosuppression following the administration of Irinotecan. The concurrent administration of Irinotecan with irradiation has not been adequately studied and is not recommended.
Lymphocytopenia has been reported in patients receiving Irinotecan, and it is possible that the administration of dexamethasone as antiemetic prophylaxis may have enhanced the likelihood of this effect. However, serious opportunistic infections have not been observed, and no complications have specifically been attributed to lymphocytopenia.
Hyperglycemia has also been reported in patients receiving Irinotecan. Usually, this has been observed in patients with a history of diabetes mellitus or evidence of glucose intolerance prior to administration of Irinotecan. It is probable that dexamethasone, given as antiemetic prophylaxis, contributed to hyperglycemia in some patients.
OVERDOSAGE
In U.S. phase 1 trials, single doses of up to 345 mg/m2 of irinotecan were administered to patients with various cancers. Single doses of up to 750 mg/m2 of irinotecan have been given in non-U.S. trials. The adverse events in these patients were similar to those reported with the recommended dosage and regimen. There have been reports of overdosage at doses up to approximately twice the recommended therapeutic dose, which may be fatal. The most significant adverse reactions reported were severe neutropenia and severe diarrhea. There is no known antidote for overdosage of Irinotecan. Maximum supportive care should be instituted to prevent dehydration due to diarrhea and to treat any infectious complications.
CONTRAINDICATIONS
ZINOTECANInjection is contraindicated in patients with a known hypersensitivity to the drug or its excipients.
Store protected from light at a temperature not exceeding 25degree Celsius.
40MG/2ML (SINGLE USE VIAL)
100MG/5ML (SINGLE USE VIAL)