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Rytelo (IMETELSTAT)
Rytelo works by inhibiting the activity of telomerase, an enzyme that helps cancer cells grow and divide.
Rytelo (imetelstat), developed by Geron, is a marketed drug targeting low- to intermediate-1 risk myelodysplastic syndromes (MDS) with transfusion-dependent anemia. Its key strength lies in its unique mechanism of action, inhibiting telomerase, which disrupts the growth and division of cancer cells. The primary risk is the key composition patent expiry in 2028, which could lead to increased competition.
At a glance
| Generic name | IMETELSTAT |
|---|---|
| Sponsor | Geron |
| Therapeutic area | Oncology |
| Phase | FDA-approved |
| First approval | 2024 |
Mechanism of action
. Mechanism of Action Imetelstat is an oligonucleotide human telomerase inhibitor that binds to the template region of the RNA component of human telomerase (hTR), inhibits telomerase enzymatic activity and prevents telomere binding. Increased telomerase activity and human telomerase reverse transcriptase (hTERT) RNA expression have been reported in MDS and malignant stem and progenitor cells. Nonclinical studies showed imetelstat treatment led to reduction of telomere length, reduction of malignant stem and progenitor cell proliferation, and induction of apoptotic cell death.
Approved indications
- Low- to Intermediate-1 Risk MDS with Transfusion-Dependent Anemia
Common side effects
- Fatigue
- Arthralgia/myalgia
- COVID-19 infections
- Headache
- Urinary tract infection
- Neutropenia
- Thrombocytopenia
- Sepsis
- Fracture
- Cardiac failure
- Hemorrhage
- Infusion-related reactions
Key clinical trials
- A Study to Find the Highest Dose of Imetelstat in Combination With Fludarabine and Cytarabine for Patients With AML, MDS or JMML That Has Come Back or Does Not Respond to Therapy (PHASE1)
- A Study to Evaluate the Safety, Pharmacokinetics, Pharmacodynamics and Clinical Activity of Imetelstat in Combination With Ruxolitinib in Participants With Myelofibrosis (PHASE1)
- Imetelstat Combinations in Relapsed AML (PHASE1)
- Study to Evaluate Imetelstat (GRN163L) in Participants With International Prognostic Scoring System (IPSS) Low or Intermediate-1 Risk Myelodysplastic Syndrome (MDS) (PHASE2,PHASE3)
- A Study Comparing Imetelstat Versus Best Available Therapy for the Treatment of Intermediate-2 or High-risk Myelofibrosis (MF) Who Have Not Responded to Janus Kinase (JAK)-Inhibitor Treatment (PHASE3)
- Investigational Drug in Combination With Two Chemotherapy Drugs in Women With Locally Recurrent or Metastatic Breast Cancer (PHASE1,PHASE2)
- Study to Evaluate Imetelstat in Patients With High-Risk MDS or AML Failing HMA-based Therapy (PHASE2)
- Expanded Access for Treatment With Imetelstat
Patents
| Patent | Expiry | Type |
|---|---|---|
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
| FDA Orange Book | Patents + exclusivity |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Rytelo CI brief — competitive landscape report
- Rytelo updates RSS · CI watch RSS
- Geron portfolio CI