Model-informed assessment of ethnic sensitivity and dosage justification for Asian populations in the global clinical development and use of cladribine tablets.

Cladribine tablets have been approved in many countries for the treatment of patients with various forms of relapsing multiple sclerosis (MS). Cladribine has a unique pharmacokinetic/pharmacodynamic (PK/PD) profile with a short elimination half-life (~ 1 day) relative to a prolonged PD effect on specific immune cells (most notably a reversible reduction in B and T lymphocyte counts). This results in a short dosing schedule (up to 20 days over 2 years of treatment) to sustain efficacy for at least another 2 years. Global clinical studies were conducted primarily in White patients, in part due to the distinctly higher prevalence of MS in White patients. Given the very low prevalence in Asian countries, MS is considered as a rare disease there. In spite of the limited participation of Asian patients, to demonstrate favorable benefit/risk profile in the treatment of MS demanded application of a Totality of Evidence approach to assess ethnic sensitivity for informing regulatory filings in Asian countries and supporting clinical use of cladribine in Asian patients. Population PD modeling and simulation of treatment-related reduction in absolute lymphocyte count, as a mechanism-related biomarker of drug effect, confirmed consistent PDs in Asian and non-Asian patients with MS, supporting absence of ethnic sensitivity and a common dosage across populations. Through this example, we demonstrate the value of holistic integration of all available data using a model-informed drug development (MIDD) framework and a Totality of Evidence mindset to evaluate ethnic sensitivity in support of Asia-inclusive development and use of the drug across populations.

Cost-effectiveness of Cladribine Tablets and fingolimod in the treatment of relapsing multiple sclerosis with high disease activity in Spain.

OBJECTIVE: To estimate the cost-effectiveness of Cladribine Tablets in the treatment of relapsing multiple sclerosis (RMS) with high disease activity compared with fingolimod, from the perspective of the National Health System (NHS) in Spain. METHODS: A Markov model was developed. The annual transition probabilities, were adjusted to patients with RMS with high disease activity. The effect of the treatments compared on the Expanded Disability Status Scale (EDSS) was modeled by hazard ratios for the confirmed progression of disability. The annual relapse rate and the probability of suffering adverse reactions were obtained from a meta-analysis and the literature. The derived costs were calculated from Spanish unit costs. The utilities were obtained from the CLARITY clinical trial and the literature. Deterministic and probabilistic sensitivity analyzes were performed. RESULTS: Cladribine tablets was the dominant treatment: lower costs (-86,536 €) and more effective (+1.11 quality-adjusted life years - QALYs) compared to fingolimod. The probability that Cladribine Tablets was cost-effective compared to fingolimod ranged between 94.6% and 96.1% for willingness to pay from € 20,000 to € 30,000 per QALY gained. CONCLUSIONS: Cladribine Tablets is a cost-effective treatment, compared to fingolimod, for the treatment of RMS with high disease activity. EXPERT OPINION: According to the present study, compared to fingolimod, treatment with Cladribine Tablets of relapsing multiple sclerosis with high disease activity is an option that could generate savings for the Spanish National Health System, with a considerable gain in QALYs. Cladribine Tablets is considered cost-effective and dominant (less costs and more effectiveness) than fingolimod treatment option in this population.

Cost Effectiveness of Cladribine Tablets for the Treatment of Relapsing-Remitting Multiple Sclerosis in The Netherlands.

BACKGROUND: Cladribine tablets have recently become available in The Netherlands for patients with relapsing-remitting multiple sclerosis (RRMS) as a disease-modifying agent that reduces the frequency and severity of relapses and delays disability progression. OBJECTIVE: The aim of this study was to evaluate the cost effectiveness of cladribine tablets, compared with alternative options, in the treatment of RRMS patients with high disease activity (HDA) and patients with rapidly evolving severe (RES) MS in The Netherlands. METHODS: A Markov model was developed simulating the costs and effects of RRMS treatment. For HDA, alemtuzumab and fingolimod were used as comparators; natalizumab was used for the RES subpopulation. The analysis included a societal perspective and a value-of-information (VOI) analysis. RESULTS: For the HDA subpopulation, treatment with cladribine tablets was the cost-effective (dominant) strategy compared with alemtuzumab and fingolimod, with 50.9% and 98.2%, respectively, probability of being cost effective at a threshold of €50,000/QALY gained and a net monetary benefit (NMB) of €10,866 and €151,115, respectively. For the RES subpopulation, treatment with cladribine tablets dominated treatment with natalizumab, with 94.1% probability of being cost effective at a threshold of €50,000/QALY gained and an NMB of €122,986. Note that these outcomes are driven by the lower costs of cladribine tablets. Efficacy differences were small, very uncertain, and likely not clinically meaningful. The probabilistic sensitivity analyses showed significant overlap in the credible intervals for total lifetime QALY outcomes and costs of cladribine tablets and all relevant comparators. The population-level VOI amounted to €19,295,441. CONCLUSIONS: The base-case analysis shows that treatment of RRMS with cladribine tablets is cost effective versus alemtuzumab and fingolimod in HDA patients, and cost effective versus natalizumab in RES patients, at a threshold of €50,000. Driven by the lower costs, cladribine tablets were cost effective (dominant) in all base-case analyses. However, given that outcomes are based on indirect comparisons and post hoc subgroup analysis, as well as the uncertainty surrounding the outcomes, the results presented in this paper should be interpreted with caution.

Cladribine Tablets for the First-Line Treatment of Relapsing-Remitting Multiple Sclerosis: An Evidence Review Group Perspective of a NICE Single Technology Appraisal.

As part of the single technology appraisal process, the National Institute for Health and Care Excellence invited Merck to submit evidence for the clinical and cost effectiveness of cladribine tablets (cladribine) for the treatment of relapsing-remitting multiple sclerosis (RRMS). Rapidly evolving severe (RES) and sub-optimally treated (SOT) RRMS were specified by the National Institute for Health and Care Excellence as subgroups of interest. The Liverpool Reviews and Implementation Group at the University of Liverpool was the Evidence Review Group. This article summarises the Evidence Review Group's review of the company's evidence submission for cladribine and the Appraisal Committee's final decision. The final scope issued by the National Institute for Health and Care Excellence listed the following disease-modifying treatments as comparators: alemtuzumab, daclizumab, fingolimod and natalizumab. At the time of the company submission, a licence was anticipated for low-dose cladribine. The main clinical evidence (the CLARITY trial) in the company submission focused on the efficacy of low-dose cladribine vs. placebo. The CLARITY trial showed a statistically significant reduction in relapse rate for cladribine in the RES-RRMS subgroup (n = 50) but not in the SOT-RRMS subgroup (n = 19). Cladribine showed a numerical, but not a statistically significant, advantage in delaying disability progression at 6 months in the RES-RRMS subgroup. Disability progression benefits could not be estimated for those in the SOT-RRMS subgroup because of few events. The Evidence Review Group's main concern regarding the clinical evidence was the small sample size of the subgroups. To compare the effectiveness of cladribine to other disease-modifying treatments, the company conducted network meta-analyses, which showed cladribine and its comparators to be equally effective. The Evidence Review Group considered the results of the disease-modifying treatments to be unreliable because few trials were in the network. The company's cost-effectiveness evidence showed cladribine to be cheaper and more effective than other disease-modifying treatments in the RES-RRMS arm and the SOT-RRMS arm. The results were most sensitive to treatment effect on disability progression at 6 months. The Evidence Review Group was concerned that there was insufficient evidence to conclude that cladribine was superior to placebo in delaying disability progression. The Evidence Review Group amended the company's economic model to allow alternative estimates for the treatment effect of cladribine and its comparators on relapse rate and disability progression at 6 months. The Evidence Review Group made other changes to the company model. After implementing all the amendments, cladribine remained cost effective in the RES-RRMS and SOT-RRMS subgroups. The Appraisal Committee recognised the uncertainty in the available data but concluded that cladribine could be considered a cost-effective use of National Health Service resources.

Treating the ineligible: Disease modification in people with multiple sclerosis beyond NHS England commissioning policies.

BACKGROUND: Whilst there is a broad selection of drugs licensed as disease modifying treatments (DMTs) for people with relapsing multiple sclerosis (pwRMS), access to DMTs remains restricted, particularly for people with progressive MS (pwPMS). Cladribine has shown efficacy at all stages of MS. Following withdrawal from the market of oral cladribine in 2011, partly due to issues associated with lymphopenia, and following a thorough risk assessment, we started using subcutaneously injected cladribine (Litak®) to treat both pwRMS and pwPMS. Here, we report on the real life safety and tolerability of this treatment option. METHODS: Cladribine was offered to (i) pwRMS as a choice despite fulfilling NHS England (NHSE) criteria for licensed DMTs, and (ii) pwRMS and pwPMS not eligible for NHSE approved DMTs. To avoid lymphocyte depletion lower than 0.5 × 109/l (WHO grade 2) cladribine was administered using a personalised dosing scheme (30-40 mg in week 1; and another 0-30 mg in week 5 pending total lymphocyte count at week 4). Anti-viral prophylaxis was given from day 1 for 60 days. Patients approaching week 48 were given a second treatment cycle. Data collection included side effects, relapses, change in disability and MRI indices. RESULTS: Seventy-one pwMS (40 female, 31 male; 36 RMS, 35 PMS,) received at least one treatment cycle. Mean age for starting cladribine was 44 years (range 22-72 years), median EDSS was 5 (range 1-8.5). Maximum follow-up was 28 months. 35/71 pwMS were followed up for at least 20 weeks. These patients had a median EDSS of 5.0 (range 1.0-7.5) at baseline and 5.5 (range 1.0-8.0) after a mean follow-up of 11 months (range 5-28). Cladribine was well tolerated with very few treatment-related adverse events observed. Personalised dosing led to grade 1-2 lymphopenia in 50% of cases. A single patient developed transient grade 3 lymphopenia. No cases of varicella or other infections were observed. Four/17 people with relapsing MS, experienced a total of six relapses during a mean follow-up of 13 months (range 5-28 months). In people with PMS (n = 18) median EDSS was 5.5 (2.0-7.5) at baseline and 6.0 (2.5-7.5) after a median of 10 months (range 5-18). In pwPMS MRI showed that 25% had active scans at baseline, and 0% at follow-up. CONCLUSION: Personalised dosing of cladribine avoided severe lymphopenia in all but one patients and was very well tolerated across a large spectrum of disease severity. Our data suggests cladribine may offer benefit people with relapsing and progressive MS alike. The personalised protocol used appears safe, however warrants controlled studies to more definitively assess efficacy and safety, particularly in groups of pwMS who are not eligible for licensed DMT including oral cladribine (Mavenclad®).

Eficacia y seguridad de cladribina en el tratamiento de pacientes con diagnóstico de tricoleucemia / Efficacy and safety of cladribine in the treatment of patients diagnosed with tricholeukemia

INTRODUCCIÓN: Antecedentes: En el present dictamen preliminar expone la evaluación de tecnología de la eficacia y seguridad del uso de cladribina en el tratamiento de pacientes adultos con diagnostico de leucemia de células vellosas o tricoleucemia. Así, los médicos hematólogos. Aspectos Generaels: La leucemia de células vellosas o tricoleucemia es una neoplasia de los linfocitos B pequeños que se caracteriza por la presencia de "células peludas" o células con núcleos ovales indentados y citoplasma abundante con proyecciones citoplasmáticas "pelulas", obervables en el 90% de los pacientes que se padecen. Los marcadores más comunes expresados por las células peludas son el CD19, CD20 y CD22, con una notable co-expressión de CD103, CD25, CD11c. Tecnologia Sanitaria de Interés: Cladribina es un agente antineoplásico sintético que se encuentra disponbile en viales para infusión endovenosa continua. METODOLOGÍA: Estrategia de Búsqueda: Se realizó una búsqueda de la literatura con respecto a la eficacia y seguridad de cladribina en el tratamiento de pacientes con tricoleucemia en las bases de datos de Medline, Embase, Scopus, Web of Science, Cinahl, Cochrane y Tripdatabase. RESULTADOS: Sinopsis de la Evidencia: Se realizó la búsqueda bibliográfica y de la evidencia que sustente el uso de cladribina en el tratamiento de la tricoleucemia según la pregunta PICO establecida. CONCLUSIONES: Rituximab ha sido empleado en EsSalud como primera linea de tratamiento frente a la falta de acceso a cladribina. Sin embargo, ciertos pacientes presentan respuesta inadecuada o intolerancia a rituximab y requieren otras alternativas de tratamiento. Adicionalmente, se ha solicitado el uso de cladribina como terapia de primera línea en pacientes con tricoleucemia dado que en la actualidad se emplea un medicamento que no se encuentra indicado como primera líena para lla condición. En base a esta solicitud se llevó a cabo una rewvisión de la literatura sobre la eficacia y seguridad de cladribina en la poblaciones de pacientes previamente tratados y no-tratados. El Instituto de Evaluación de Tecnologías en Salud e Investigación-IETSI aprueba el uso de cladribina como alternativa de tratamiento en pacientes con tricoleucemia previamente tratados o como primera línea de tratamiento. El perído de vigencia del presente dictamen preliminar es de dos años y la continuación de dicha aprobación estará sujeta a los resultados obtenidos de los pacientes que se beneficien con dicho tratamiento y a nueva evidencia que pueda surgir en el tiempo.

Toward personalized therapy for chronic lymphocytic leukemia: DSC and cDNA microarray assessment of two cases.

The differences in clinical course of chronic lymphocytic leukemia could have an impact on variations in a patient's response to therapy. Our published results revealed that thermal transition (95 ± 5°C) in differential scanning calorimetry profiles appear to be characteristic for the advanced stage of CLL. Moreover, a decrease/loss of this transition in nuclei from leukemic cells exposed to drugs ex vivo could indicate their diverse efficacy. It seems that the lack of changes in thermal profile could predict patient's drug resistance. In this study, we demonstrate the results obtained after drug treatment of leukemic cells by calorimetry, apoptosis-related parameters involved in expression of genes using cDNA microarray and western blot. These data were compared with the patients' clinical parameters before and after RCC therapy (rituximab + cladribine + cyclophosphamide). The complementary analysis of studied cases with opposite clinical response (CR or NR) revealed a strong relationship between clinical data, differences in thermal scans and apoptosis-related gene expression. We quantified expression of eight of apoptosis-related 89 genes, i.e., NOXA, PUMA, APAF1, ESRRBL1, CASP3, BCL2, BCL2A1 and MCL1. Particular differences in NOXA and BCL2 expression were revealed. NOXA expression in cells of patients who achieved a complete response to RCC therapy was 0.44 times higher in comparison to control ones. Interestingly, in the case of patients who did not respond to immunotherapy, NOXA expression was highly downregulated (RQ = 4.39) as compared with untreated cells. These results were confirmed by distinct cell viability, protein expression as well as by differences in calorimetry profiles.

Treatment of hairy cell leukemia: long-term results in a developing country.

Twenty-nine consecutive patients with hairy cell leukemia (HCL) were treated in two institutions with interferon (IFN, n = 18) or cladribine (n = 11), between July 1987 and May 2011. Median age was 62 (range 29-83) years; there were 21 males and 8 females. Seven of the 18 patients in the IFN group (39%) achieved a complete remission (CR), whereas all the patients in the 2-CDA group entered a CR. Three patients in the 2-CDA group relapsed and needed an additional course of the drug, 2, 3 and 6 years after the initial one. The median overall survival (OS) of the whole group has not been reached, being above 217 months, the 217-month OS being 91%. The survival of patients treated with either IFN or 2-CDA was not statistically different (94% OS at 217 months versus 91% OS at 133 months, respectively). The data that we present here suggest that treatment of HCL with either 2-CDA or IFN is equally effective; treatment costs with IFN are substantially lower than those of the purine analog.

Cladribine for the treatment of hematologic malignancies.

The mechanism of action, pharmacokinetics, efficacy, adverse effects, storage, dosage and administration, and cost of cladribine are reviewed. Cladribine (2-chloro-2'-deoxyadenosine) is a synthetic purine nucleoside developed for the treatment of hematologic malignancies. It appears that cladribine interferes with lymphocyte proliferation by inhibiting DNA repair. The pharmacokinetics of cladribine best fit a two-compartment, first-order-elimination model. Of the conditions that have been treated with cladribine, hairy cell leukemia (HCL) has shown the most dramatic response. Overall response rates in clinical studies have ranged from 80% to 100%, with a large majority of these being complete remissions; median durations of responses have ranged from about 9 to 16 months. Other conditions that have responded to cladribine are chronic lymphocytic leukemia (CLL), acute leukemia, chronic myeloid leukemia, low-grade lymphomas, Waldenström's macroglobulinemia, and cutaneous T-cell lymphoma. The drug is inactive against solid tumors. The principal dose-limiting adverse effect of cladribine is bone marrow suppression; fever, immunosuppression, renal and neurologic effects, and local skin reactions have also been reported. The drug is typically administered as an extended continuous i.v. infusion. The usual dosage for treating HCL is 0.1 mg/kg/day for seven days. The estimated cost of cladribine for treating an average patient with HCL is $3500. Cladribine has shown efficacy against a variety of hematologic malignancies, notably HCL and CLL.