Low- to Intermediate-Risk Myelodysplastic Syndromes
The safety of RYTELO was evaluated in a randomized, double-blind, placebo-controlled, multicenter trial (IMerge) in 177 adult patients with International Prognostic Scoring System (IPSS) low- to intermediate-1 risk MDS who were transfusion-dependent and relapsed or refractory to or ineligible for ESA treatment [see Clinical Studies (14)]. The safety population included patients who received at least one dose of either RYTELO (n=118) or placebo (n=59) at 7.1 mg/kg as an intravenous infusion administered over two hours every 4 weeks. The median time on treatment with RYTELO was 8 months (range, 0 to 38 months); 69% of patients were exposed to RYTELO for 24 weeks or longer and 45% were exposed for 48 weeks or longer.
The median age of patients who received at least one dose of RYTELO was 72 years (range: 44 to 87 years) with 77% of patients 65 years of age and older and 30% of patients 75 years of age and older. Participants were 60% male, 81% White, 7% Asian, and 0.8% Black.
Serious adverse reactions occurred in 32% of patients who received RYTELO. Serious adverse reactions in > 2% of patients included sepsis (4.2%), fracture (3.4%), cardiac failure (2.5%), and hemorrhage (2.5%). Fatal adverse reactions occurred in 0.8% of patients who received RYTELO, including sepsis (0.8%).
Permanent discontinuation of RYTELO due to an adverse reaction occurred in 15% of patients. Adverse reactions which resulted in permanent discontinuation of RYTELO in > 2% of patients included neutropenia and thrombocytopenia.
Dosage interruptions of RYTELO due to an adverse reaction occurred in 80% of patients. Adverse reactions which required dosage interruption in > 5% of patients included neutropenia, thrombocytopenia and infections.
Dose reductions of RYTELO due to an adverse reaction occurred in 49% of patients. Adverse reactions which required dose reductions in > 2% of patients included neutropenia and thrombocytopenia.
The most common (≥10% with a difference between arms of >5% compared to placebo) adverse reactions, including laboratory abnormalities, were decreased platelets, decreased white blood cells, decreased neutrophils, increased AST, increased alkaline phosphatase, increased ALT, fatigue, prolonged partial thromboplastin time, arthralgia/myalgia, COVID-19 infections, and headache.
Table 5 summarizes the adverse reactions in IMerge.
Table 5: Adverse Reactions (≥5%) in Patients with MDS Who Received RYTELO with a Difference Between Arms of >2% Compared to Placebo in IMerge| Adverse Reaction | RYTELO (N=118) | Placebo (N=59) |
|---|
| All Grades % | Grades 3 or 4 % | All Grades % | Grades 3 or 4 % |
|---|
| Graded according to National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.03. |
| General disorders and administrative site conditions |
| Fatigue
| 29 | 0 | 20 | 3.4 |
| Musculoskeletal and connective tissue disorders |
| Arthralgia/myalgia
| 25 | 2.5 | 19 | 5 |
| Infections and infestations |
| COVID-19
| 19 | 1.7 | 14 | 5 |
| Urinary tract infection
| 9 | 2.5 | 7 | 0 |
| Nervous system disorders |
| Headache | 13 | 0.8 | 5 | 0 |
| Syncope
| 7 | 1.7 | 1.7 | 0 |
| Immune system disorders |
| Infusion-related reactions
| 8 | 1.7 | 3.4 | 0 |
| Respiratory, thoracic and mediastinal disorders |
| Epistaxis | 7 | 0 | 0 | 0 |
| Vascular disorders |
| Hematoma | 6 | 0 | 0 | 0 |
| Skin and subcutaneous tissue disorders |
| Pruritus | 6 | 0 | 1.7 | 0 |
| Cardiac disorders |
| Atrial arrhythmia
| 6 | 1.7 | 3.4 | 1.7 |
| Injury, poisoning and procedural complications |
| Fractures
| 5 | 3.4 | 1.7 | 1.7 |
Clinically relevant adverse reactions in < 5% of patients who received RYTELO included febrile neutropenia, sepsis, gastrointestinal hemorrhage, and hypertension.
Table 6 summarizes the laboratory abnormalities in IMerge.
Table 6: Select Laboratory Abnormalities (≥10%) That Worsened from Baseline in Patients with MDS Who Received RYTELO with a Difference Between Arms of >2% Compared to Placebo in IMerge| Laboratory Abnormality | RYTELO
| Placebo
|
|---|
| All Grades (%) | Grade 3 or 4 (%) | All Grades (%) | Grade 3 or 4 (%) |
|---|
Graded according to National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.03. ALP = alkaline phosphatase; ALT = alanine aminotransferase; AST = aspartate aminotransferase; PTT = partial thromboplastin time |
| Hematology |
| Platelet count decreased | 97 | 65 | 34 | 8 |
| White blood cell count decreased | 94 | 53 | 59 | 1.7 |
| Neutrophil count decreased | 92 | 72 | 47 | 7 |
| PTT prolonged | 26 | 1 | 18 | 4 |
| Chemistry |
| AST increased | 53 | 0.8 | 22 | 1.7 |
| ALP increased | 48 | 0 | 12 | 0 |
| ALT increased | 43 | 3.4 | 37 | 5 |