Treatment patterns and outcomes of second-line rituximab and thrombopoietin receptor agonists in adult immune thrombocytopenia: A Canadian retrospective cohort study.
The optimal choice of second-line treatment for immune thrombocytopenia (ITP) is unclear. Guidelines recommend either rituximab, splenectomy, or thrombopoietin receptor agonists (TPO-RA). There is, however, scarce data comparing treatment patterns, outcomes and resource utilization across second-line treatments. Despite Canada's universal healthcare system, publicly funded access to second-line ITP therapies is highly variable across provinces/territories.
To describe treatment patterns and compare health service utilization and outcomes among recipients of second-line rituximab and TPO-RA for ITP.
In this multicentre retrospective cohort study, we included adults who received second-line ITP therapies rituximab, eltrombopag and romiplostim (2012-2020) in Alberta, Canada. Patients were identified through a provincially-funded special drug access (STEDT) program. We examined treatment patterns, predictors of second-line treatment, hospitalizations, blood product utilization, and outcomes. Kaplan-Meier survival curves were used to estimate the cumulative incidence of ITP-related hospitalizations (bleeding or infections), overall survival (OS) and relapse-free survival (RFS). Cox proportional hazards regression was used to examine the impact of second-line therapy on OS.
223 patients received rituximab (67 %), eltrombopag (29 %), and romiplostim (4 %). TPO-RA recipients experienced significantly longer time from ITP diagnosis to second-line therapy compared with rituximab recipients (15.9 vs 6.7 months, P < 0.0001), accompanied by significantly higher platelet and IVIG utilization prior to second-line therapy. Age (adjusted odds ratio [aOR] 1.04, 95 % CI 1.02-1.07, P < 0.0001) and prior intracranial hemorrhage (aOR 12.7, 95 % CI 1.6-272.8, P = 0.03) were significant predictors of second-line TPO-RA. TPO-RA is associated with a trend towards longer median RFS (6.3 vs 3.8 years, P = 0.06) compared with rituximab, and similar rates of ITP-related hospitalizations, major bleeding, and thromboembolism. Age, time period, and Charlson comorbidity index, but not second-line ITP therapy, were significant predictors of OS.
Our study identified older age and intracranial hemorrhage as predictors of second-line TPO-RA prescription in a real-world practice. There were no significant differences in hospitalizations and outcomes between second-line rituximab and TPO-RA, although delayed initiation of TPO-RA was associated with higher blood product utilization.
Podstawka J
，Wall E
，Bolster L
，Patterson JM
，Goodyear MD
，Rydz N
，Sun HL
... -
《-》
Treatment efficacy for adult persistent immune thrombocytopenia: a systematic review and network meta-analysis.
Persistent immune thrombocytopenia (ITP) patients require second-line treatments, for which information on clinical outcomes are lacking. A systematic review and network meta-analysis (NMA) were conducted. Only randomised controlled trials (RCT) of second-line drugs in adult persistent ITP patients with platelet response, platelet count, any bleeding or serious adverse events (SAE) outcome were eligible. Twelve RCTs (n = 1313) were included in NMA. For platelet response outcome, eltrombopag and romiplostin were the best relative to placebo; the former had a non-significant advantage [risk ratio (RR) = 1·10 (95% confidence interval: 0·46, 2·67)]. Both treatments were superior to rituximab and recombinant human thrombopoietin (rhTPO)+rituximab, with corresponding RRs of 4·56 (1·89, 10·96) and 4·18 (1·21, 14·49) for eltrombopag; 4·13 (1·56, 10·94) and 3·79 (1·02, 14·09) for romiplostim. For platelet count, romiplostim ranked highest, followed by eltrombopag, rhTPO+rituximab, and rituximab. For bleeding, rituximab had lowest risk, followed by eltrombopag and romiplostim. For SAEs, rhTPO+rituximab had highest risk, followed by rituximab, eltrombopag and romiplostim. From clustered ranking, romiplostim had the best balance between short-term efficacy and SAEs, followed by eltrombopag. In conclusion, romiplostim and eltrombopag may yield high efficacy and safety. Rituximab may not be beneficial due to lower efficacy and higher complications compared with the thrombopoietin receptor agonists. RCTs with long-term clinical outcomes are required.
Puavilai T
，Thadanipon K
，Rattanasiri S
，Ingsathit A
，McEvoy M
，Attia J
，Thakkinstian A
... -
《-》
The Cost-effectiveness of Eltrombopag for the Treatment of Immune Thrombocytopenia in the United States.
Eltrombopag was evaluated as a second-line treatment for adult chronic immune thrombocytopenia (ITP) in the 2006 Phase III RAISE (Eltrombopag for Management of Chronic Immune Thrombocytopenia) randomized, placebo-controlled trial. More than 80% of patients reached satisfactory platelet counts within 2 weeks. However, the economic value of eltrombopag as a second-line treatment for ITP remains to be formally assessed. This study aimed to estimate the cost-effectiveness of treating ITP with a comparable thrombopoietin receptor agonist (eltrombopag vs romiplostim).
A Markov model was implemented over a lifetime time horizon to estimate the benefits and costs of each treatment. The model featured 3 health states based on current guidelines: (1) on treatment; (2) treatment failure/discontinuation; and (3) mortality. In line with therapeutic goals in ITP, model patients could experience 3 events: no bleeding, mild/moderate bleeding, or severe bleeding. Data on eltrombopag use were obtained from an open-label extension of previous Phase II/III trials, including RAISE. Romiplostim data were obtained from Phase III trials and an extension study. Lifetime overall survival was extrapolated by using treatment-specific mortality rates derived from severe bleeding and natural mortality rates. The costs of drugs, routine care, bleeding episodes, adverse events, and mortality were represented in the model.
Eltrombopag-treated patients gained 17.58 life years and 14.68 quality-adjusted life years, whereas romiplostim-treated patients gained 17.52 life years and 14.67 quality-adjusted life years. The total lifetime cost of eltrombopag treatment was estimated at $1.58 million versus $2.13 million for romiplostim. Sensitivity analyses supported base case findings. Deterministic sensitivity analysis predicted the greatest sensitivity to the rates of severe bleeding, discontinuation, and natural mortality. Probabilistic sensitivity analysis showed that eltrombopag would be an efficient use of resources at a $50,000 threshold in 52.8% of cases. In all probabilistic iterations, the total cost of eltrombopag treatment was lower than with romiplostim, primarily because of lower drug costs.
Clinical data were applied in an economic analysis, and eltrombopag exhibited economic dominance compared with romiplostim, driven largely by the reduced costs of primary therapy. This model was limited by a lack of specific patient-level data and robust data on the duration of secondary therapy, as well as by the fact that utilization values are likely conservative estimates for routine care use.
Tremblay G
，Dolph M
，Roy AN
，Said Q
，Forsythe A
... -
《-》
ResearchGate
(全网免费下载)
钛学术
(全网免费下载)
