Version July 2025
Dosage guidance
Dosage form information: Synribo has been discontinued in the United States >1 year.
Chronic myeloid leukemia, chronic or accelerated phase (resistant or intolerant):
Induction: SUBQ: 1.25 mg/m2 twice daily for 14 consecutive days of a 28-day treatment cycle; continue until hematologic response is achieved (Ref).
Maintenance: SUBQ: 1.25 mg/m2 twice daily for 7 consecutive days of a 28-day treatment cycle; continue until disease progression or unacceptable toxicity (Ref).
Missed doses: If a dose is missed, skip that dose and resume with the next regularly scheduled dose. Do not administer 2 doses at the same time to make up for a missed dose.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer’s labeling (has not been studied). Based on the minimal amount of unchanged drug excreted in the urine, dosage adjustment is not likely necessary (Ref) and no need for dosage adjustment is expected (Ref).
Hemodialysis: No need for dosage adjustment is expected (Ref).
There are no dosage adjustments provided in the manufacturer’s labeling (has not been studied). However, no need for dosage adjustment is expected (Ref).
American Society of Clinical Oncology guidelines for appropriate systemic therapy dosing in adults with cancer with a BMI ≥30 kg/m2: Utilize patient's actual body weight for calculation of BSA- or weight-based dosing; manage regimen-related toxicities in the same manner as for patients with a BMI <30 kg/m2; if a dose reduction is utilized due to toxicity, may consider resumption of full, weight-based dosing (or previously tolerated dose level) with subsequent cycles only if dose escalations are allowed in the prescribing information, if contributing underlying factors (eg, hepatic or kidney impairment) are sufficiently resolved, AND if performance status has markedly improved or is considered adequate (Ref).
Hematologic toxicity: May delay treatment cycles and/or reduce the number of treatment days during a cycle for hematologic toxicities.
Neutropenia grade 4 (ANC <500/mm3) or thrombocytopenia ≥ grade 3 (platelets <50,000/mm3) during a cycle: Delay the start of the next cycle until ANC ≥1000/mm3 and platelets ≥50,000/mm3 AND reduce the number of treatment days by 2 days (eg, reduce from 14 days to 12 days or reduce from 7 days to 5 days).
Nonhematologic toxicity: Manage symptomatically; interrupt and/or delay treatment until toxicity resolves.
Refer to adult dosing.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
>10%:
Cardiovascular: Peripheral edema (16%)
Central nervous system: Fatigue (29% to 31%), headache (13% to 20%), chills (13%), insomnia (12%)
Dermatologic: Alopecia (15%), skin rash (11%)
Endocrine & metabolic: Increased uric acid (grades 3/4: 56% to 57%), hyperglycemia (grades 3/4: 10% to 15%; hyperosmolar nonketotic hyperglycemia <1%)
Gastrointestinal: Diarrhea (35% to 41%), nausea (29% to 35%), abdominal pain (16% to 23%), vomiting (12% to 15%), constipation (14%), anorexia (10% to 13%)
Hematologic & oncologic: Thrombocytopenia (58% to 76%; grades 3/4: 49% to 88%), neutropenia (20% to 53%; grades 3/4: 18% to 81%), anemia (51% to 61%; grades 3/4: 36% to 80%), leukocyte disorder (decreased: grades 3/4: 61% to 72%), febrile neutropenia (10% to 20%; grades 3/4: 10% to 16%), lymphocytopenia (17%; grades 3/4: 16%)
Infection: Infection (46% to 56%; grades 3/4: 11% to 20%)
Local: Injection site reaction (22% to 35%; includes edema, erythema, hematoma, hemorrhage, hypersensitivity, induration, inflammation, infusion related reaction, irritation, mass, pruritus, rash)
Neuromuscular & skeletal: Weakness (23% to 24%), arthralgia (19%), limb pain (11% to 13%), back pain (12%), myalgia (11%)
Renal: Increased serum creatinine (grades 3/4: 9% to 16%)
Respiratory: Epistaxis (11% to 17%), cough (≤16%), dyspnea (11%)
Miscellaneous: Fever (25% to 29%)
1% to 10%:
Cardiovascular: Acute coronary syndrome, angina pectoris, bradycardia, cardiac arrhythmia, chest pain, edema, hypertension, hypotension, palpitations, tachycardia, ventricular premature contractions
Central nervous system: Agitation, anxiety, cerebral hemorrhage, confusion, depression, dizziness, hyperthermia, hypoesthesia, lethargy, malaise, mental status changes, mouth pain, myasthenia, pain, paresthesia, sciatica, seizure, voice disorder
Dermatologic: Burning sensation of skin, dermal ulcer, desquamation, erythema, hyperhidrosis, hyperpigmentation, night sweats, pruritus, skin lesion, xeroderma
Endocrine & metabolic: Decreased serum glucose (grades 3/4: 6% to 8%), dehydration, diabetes mellitus, gout, hot flash
Gastrointestinal: Abdominal distention, anal fissure, aphthous stomatitis, decreased appetite, dysgeusia, dyspepsia, dysphagia, gastritis, gastroesophageal reflux disease, gastrointestinal hemorrhage, gingival hemorrhage, gingival pain, gingivitis, hemorrhoids, melena, mucosal inflammation, oral mucosa ulcer, stomatitis, xerostomia
Genitourinary: Dysuria
Hematologic & oncologic: Bone marrow failure (10%; grades 3/4: 10%), bruise, hematoma, hemorrhage (ear), oral hemorrhage, petechia, purpura
Hepatic: Increased serum bilirubin (grades 3/4: 6% to 9%), increased serum ALT (grades 3/4: 2% to 6%)
Hypersensitivity: Hypersensitivity reaction, transfusion reaction
Neuromuscular & skeletal: Muscle spasm, musculoskeletal chest pain, musculoskeletal pain (or discomfort), ostealgia, stiffness, tremor
Ophthalmic: Blurred vision, cataract, conjunctival hemorrhage, conjunctivitis, diplopia, eyelid edema, eye pain, increased lacrimation, xerophthalmia
Otic: Otalgia, tinnitus
Respiratory: Flu-like symptoms, hemoptysis, nasal congestion, pharyngolaryngeal pain, rales, rhinorrhea, sinus congestion
There are no contraindications listed in the manufacturer’s labeling.
Concerns related to adverse effects:
• Bone marrow suppression: Grade 3/4 neutropenia, thrombocytopenia and anemia commonly occur; generally reversible, although may require treatment delay and/or a reduction in the number of treatment days with future cycles. Myelosuppression may rarely be fatal. Neutropenia may increase the risk for infection. Thrombocytopenia may increase the risk of bleeding; cerebrovascular hemorrhages have been reported (some fatal); gastrointestinal hemorrhages have occurred. Due to the increased risk of bleeding, avoid the use of anticoagulants, aspirin, and NSAIDs when the platelet count is <50,000/mm3.
• Glucose intolerance: Omacetaxine may induce glucose intolerance. Hyperglycemia (including grade 3 and 4 events) has been observed; hyperosmolar nonketotic hyperglycemia has been reported (case report). Avoid use in patients with poorly controlled diabetes; may initiate after glycemic control has been established.
Special populations:
• Older adult: Patients ≥65 years of age are more likely to experience toxicity, especially hematologic toxicity.
Synribo has been discontinued in the United States >1 year.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Solution Reconstituted, Subcutaneous, as mepesuccinate [preservative free]:
Synribo: 3.5 mg (1 ea [DSC])
No
Solution (reconstituted) (Synribo Subcutaneous)
3.5 mg (per each): $1,597.08
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
SUBQ: Administer SUBQ at approximately 12 hour intervals. If home administration is to occur, advise patient on proper handling, storage conditions, administration, disposal, and clean-up of accidental spillage; ensure that the patient or patient’s caregiver is an appropriate candidate for home administration. Avoid skin and eye contact; wear protective eyewear and gloves during handling and administration.
Hazardous agent (NIOSH 2024 [table 1]).
Use appropriate precautions for receiving, handling, storage, preparation, dispensing, transporting, administration, and disposal. Follow NIOSH and USP 800 recommendations and institution-specific policies/procedures for appropriate containment strategy (NIOSH 2023; NIOSH 2024; USP-NF 2020).
An FDA-approved patient medication guide, which is available with the product information and at https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/203585s007lbl.pdf#page=16, must be dispensed with this medication.
Chronic myeloid leukemia, chronic or accelerated phase: Treatment of chronic or accelerated phase chronic myeloid leukemia (CML) in adults with resistance and/or intolerance to 2 or more tyrosine kinase inhibitors.
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drug classes (chemotherapeutic agent, parenteral and oral) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Acute Care, Community/Ambulatory Care, and Long-Term Care Settings).
Substrate of P-glycoprotein (Minor); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential;
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
5-Aminosalicylic Acid Derivatives: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Abrocitinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Anticoagulants: May increase adverse/toxic effects of Omacetaxine. Specifically, the risk for bleeding-related events may be increased. Management: Avoid concurrent use of anticoagulants with omacetaxine in patients with a platelet count of less than 50,000/uL. Risk X: Avoid
Antidiabetic Agents: Hyperglycemia-Associated Agents may decrease therapeutic effects of Antidiabetic Agents. Risk C: Monitor
Antithymocyte Globulin (Equine): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Antithymocyte Globulin (Equine). Specifically, these effects may be unmasked if the dose of immunosuppressive therapy is reduced. Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Antithymocyte Globulin (Equine). Specifically, infections may occur with greater severity and/or atypical presentations. Risk C: Monitor
Antithyroid Agents: Myelosuppressive Agents may increase neutropenic effects of Antithyroid Agents. Risk C: Monitor
Aspirin: May increase adverse/toxic effects of Omacetaxine. Specifically, the risk for bleeding-related events may be increased. Management: Avoid concurrent use of aspirin with omacetaxine in patients with a platelet count of less than 50,000/uL. Risk X: Avoid
Baricitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Baricitinib. Risk X: Avoid
BCG Products: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of BCG Products. Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of BCG Products. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Brincidofovir: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Brincidofovir. Risk C: Monitor
Brivudine: May increase adverse/toxic effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Chikungunya Vaccine (Live): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Chikungunya Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Chikungunya Vaccine (Live). Risk X: Avoid
Chloramphenicol (Ophthalmic): May increase adverse/toxic effects of Myelosuppressive Agents. Risk C: Monitor
Chloramphenicol (Systemic): Myelosuppressive Agents may increase myelosuppressive effects of Chloramphenicol (Systemic). Risk X: Avoid
Cladribine: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Cladribine. Risk X: Avoid
CloZAPine: Myelosuppressive Agents may increase adverse/toxic effects of CloZAPine. Specifically, the risk for neutropenia may be increased. Risk C: Monitor
Coccidioides immitis Skin Test: Coadministration of Immunosuppressants (Miscellaneous Oncologic Agents) and Coccidioides immitis Skin Test may alter diagnostic results. Management: Consider discontinuing these oncologic agents several weeks prior to coccidioides immitis skin antigen testing to increase the likelihood of accurate diagnostic results. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Inactivated Virus): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of COVID-19 Vaccine (Inactivated Virus). Risk C: Monitor
COVID-19 Vaccine (mRNA): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of COVID-19 Vaccine (mRNA). Management: Give a 3-dose primary series for all patients aged 6 months and older taking immunosuppressive medications or therapies. Booster doses are recommended for certain age groups. See CDC guidance for details. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Subunit): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of COVID-19 Vaccine (Subunit). Risk C: Monitor
Deferiprone: Myelosuppressive Agents may increase neutropenic effects of Deferiprone. Management: Avoid the concomitant use of deferiprone and myelosuppressive agents whenever possible. If this combination cannot be avoided, monitor the absolute neutrophil count more closely. Risk D: Consider Therapy Modification
Dengue Tetravalent Vaccine (Live): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Dengue Tetravalent Vaccine (Live). Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Dengue Tetravalent Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Denosumab: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Management: Consider the risk of serious infections versus the potential benefits of coadministration of denosumab and immunosuppressants. If combined, monitor patients for signs/symptoms of serious infections. Risk D: Consider Therapy Modification
Deucravacitinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Etrasimod: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Fexinidazole: Myelosuppressive Agents may increase myelosuppressive effects of Fexinidazole. Risk X: Avoid
Filgotinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Inebilizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Inebilizumab. Risk C: Monitor
Influenza Virus Vaccines: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Influenza Virus Vaccines. Management: Administer influenza vaccines at least 2 weeks prior to initiating immunosuppressants if possible. If vaccination occurs less than 2 weeks prior to or during therapy, revaccinate at least 3 months after therapy discontinued if immune competence restored. Risk D: Consider Therapy Modification
Leflunomide: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Leflunomide. Management: Increase the frequency of chronic monitoring of platelet, white blood cell count, and hemoglobin or hematocrit to monthly, instead of every 6 to 8 weeks, if leflunomide is coadministered with immunosuppressive agents. Risk D: Consider Therapy Modification
Linezolid: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Mumps- Rubella- or Varicella-Containing Live Vaccines: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Mumps- Rubella- or Varicella-Containing Live Vaccines may increase adverse/toxic effects of Immunosuppressants (Miscellaneous Oncologic Agents). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Nadofaragene Firadenovec: Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Nadofaragene Firadenovec. Specifically, the risk of disseminated adenovirus infection may be increased. Risk X: Avoid
Natalizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Natalizumab. Risk X: Avoid
Nonsteroidal Anti-Inflammatory Agents: May increase adverse/toxic effects of Omacetaxine. Specifically, the risk for bleeding-related events may be increased. Risk C: Monitor
Ocrelizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ocrelizumab. Risk C: Monitor
Ofatumumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ofatumumab. Risk C: Monitor
Olaparib: Myelosuppressive Agents may increase myelosuppressive effects of Olaparib. Risk C: Monitor
Pidotimod: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Pidotimod. Risk C: Monitor
Pimecrolimus: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid
Pneumococcal Vaccines: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Pneumococcal Vaccines. Risk C: Monitor
Poliovirus Vaccine (Live/Trivalent/Oral): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Polymethylmethacrylate: Immunosuppressants (Miscellaneous Oncologic Agents) may increase hypersensitivity effects of Polymethylmethacrylate. Management: Use caution when considering use of bovine collagen-containing implants such as the polymethylmethacrylate-based Bellafill brand implant in patients who are receiving immunosuppressants. Consider use of additional skin tests prior to administration. Risk D: Consider Therapy Modification
Promazine: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Rabies Vaccine: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Rabies Vaccine. Management: Complete rabies vaccination at least 2 weeks before initiation of immunosuppressant therapy if possible. If combined, check for rabies antibody titers, and if vaccination is for post exposure prophylaxis, administer a 5th dose of the vaccine. Risk D: Consider Therapy Modification
Ritlecitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ritlecitinib. Risk X: Avoid
Ropeginterferon Alfa-2b: Myelosuppressive Agents may increase myelosuppressive effects of Ropeginterferon Alfa-2b. Management: Avoid coadministration of ropeginterferon alfa-2b and other myelosuppressive agents. If this combination cannot be avoided, monitor patients for excessive myelosuppressive effects. Risk D: Consider Therapy Modification
Ruxolitinib (Topical): Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ruxolitinib (Topical). Risk X: Avoid
Sipuleucel-T: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Sipuleucel-T. Management: Consider reducing the dose or discontinuing the use of immunosuppressants prior to initiating sipuleucel-T therapy. Risk D: Consider Therapy Modification
Sphingosine 1-Phosphate (S1P) Receptor Modulators: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk C: Monitor
Tacrolimus (Topical): Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Tacrolimus (Topical). Risk X: Avoid
Talimogene Laherparepvec: Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Talimogene Laherparepvec. Specifically, the risk of infection from the live, attenuated herpes simplex virus contained in talimogene laherparepvec may be increased. Risk X: Avoid
Tertomotide: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Tertomotide. Risk X: Avoid
Tofacitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Tofacitinib. Risk X: Avoid
Typhoid Vaccine: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Typhoid Vaccine. Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Typhoid Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Ublituximab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ublituximab. Risk C: Monitor
Upadacitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Upadacitinib. Risk X: Avoid
Vaccines (Live): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Vaccines (Live). Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Vaccines (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Vaccines (Non-Live/Inactivated/Non-Replicating): Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Vaccines (Non-Live/Inactivated/Non-Replicating). Management: Give non-live/inactivated/non-replicating vaccines at least 2 weeks prior to initiation of immunosuppressants when possible. Patients vaccinated less than 14 days before or during therapy should be revaccinated at least 3 months after therapy is complete. Risk D: Consider Therapy Modification
Yellow Fever Vaccine: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Yellow Fever Vaccine. Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Yellow Fever Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Zoster Vaccine (Live/Attenuated): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Zoster Vaccine (Live/Attenuated). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Zoster Vaccine (Live/Attenuated). Risk X: Avoid
Evaluate pregnancy status prior to use in patients who could become pregnant. Patients who could become pregnant should use effective contraception during therapy and for 6 months after the last omacetaxine dose. Patients with partners who could become pregnant should use effective contraception during therapy and for 3 months after the last dose of omacetaxine.
Based on the mechanism of action and data from animal reproduction studies, omacetaxine may cause fetal harm if administered during pregnancy.
It is not known if omacetaxine is present in breast milk.
Due to the potential for serious adverse reactions in the breastfed infant, the manufacturer does not recommend breastfeeding during therapy and for 2 weeks after the last dose of omacetaxine.
CBC with differential and platelets (weekly during induction and initial maintenance cycles, then every 2 weeks or as clinically indicated after initial maintenance cycles); blood glucose (frequently, especially in patients with diabetes or with risk factors for diabetes). Evaluate pregnancy status prior to use in patients who could become pregnant. Monitor for signs/symptoms of infection and signs of bleeding.
The American Society of Clinical Oncology hepatitis B virus (HBV) screening and management provisional clinical opinion (ASCO [Hwang 2020]) recommends HBV screening with hepatitis B surface antigen, hepatitis B core antibody, total Ig or IgG, and antibody to hepatitis B surface antigen prior to beginning (or at the beginning of) systemic anticancer therapy; do not delay treatment for screening/results. Detection of chronic or past HBV infection requires a risk assessment to determine antiviral prophylaxis requirements, monitoring, and follow-up.
Omacetaxine is a reversible protein synthesis inhibitor which binds to the A-site cleft of the ribosomal subunit to interfere with chain elongation and inhibit protein synthesis. It acts independently of BCR-ABL1 kinase-binding activity, and has demonstrated activity against tyrosine kinase inhibitor-resistant BCR-ABL mutations.
Onset:
Chronic phase CML: Mean time to major cytogenetic response: 3.5 months.
Accelerated phase CML: Mean time to response: 2.3 months.
Duration:
Chronic phase CML: Median duration of major cytogenetic response: 12.5 months.
Accelerated phase CML: Median duration of major hematologic response: 4.7 months.
Absorption: SUBQ: Rapid (Nemunaitis 2013).
Distribution: Vdss: 141 ± 93.4 L.
Protein binding: ≤50%.
Metabolism: Hydrolyzed by plasma esterases to 4’-DMHHT; minimal hepatic metabolism.
Half-life elimination: 14.6 hours.
Time to peak: SUBQ: ~30 minutes.
Excretion: Urine (~37); feces (~44%).
