Pulmonary arterial hypertension in a chronic lymphocytic leukemia patient in treatment with rituximab

Safety and Efficacy of B-Cell Depletion with Rituximab for the Treatment of Systemic Sclerosis-associated Pulmonary Arterial Hypertension: A Multicenter, Double-Blind, Randomized, Placebo-controlled Trial

Rationale: Systemic sclerosis (SSc)-pulmonary arterial hypertension (PAH) is one of the most prevalent and deadly forms of PAH. B cells may contribute to SSc pathogenesis. Objectives: We investigated the safety and efficacy of B-cell depletion for SSc-PAH. Methods: In an NIH-sponsored, multicenter, double-blinded, randomized, placebo-controlled, proof-of-concept trial, 57 patients with SSc-PAH on stable-dose standard medical therapy received two infusions of 1,000 mg rituximab or placebo administered 2 weeks apart. The primary outcome measure was the change in 6-minute-walk distance (6MWD) at 24 weeks. Secondary endpoints included safety and invasive hemodynamics. We applied a machine learning approach to predict drug responsiveness. Measurements and Main Results: We randomized 57 subjects from 2010 to 2018. In the primary analysis, using data through Week 24, the adjusted mean change in 6MWD at 24 weeks favored the treatment arm but did not reach statistical significance (23.6 ± 11.1 m vs. 0.5 ± 9.7 m; P = 0.12). Although a negative study, when data through Week 48 were also considered, the estimated change in 6MWD at Week 24 was 25.5 ± 8.8 m for rituximab and 0.4 ± 7.4 m for placebo (P = 0.03). Rituximab treatment appeared to be safe and well tolerated. Low levels of RF (rheumatoid factor), IL-12, and IL-17 were sensitive and specific as favorable predictors of a rituximab response as measured by an improved 6MWD (receiver operating characteristic area under the curve, 0.88-0.95). Conclusions: B-cell depletion therapy is a potentially effective and safe adjuvant treatment for SSc-PAH. Future studies in these patients can confirm whether the identified biomarkers predict rituximab responsiveness. Clinical trial registered with www.clinicaltrails.gov (NCT01086540).

Severe but reversible pulmonary hypertension in scleromyxedema and multiple myeloma: a case report

BACKGROUND

Scleromyxedema is a progressive, systemic connective tissue disorder characterized by fibro-mucous skin lesions and increased serum monoclonal immunoglobulin levels. Pulmonary involvement occurs in a subset of patients, though the overall prevalence of pulmonary lesions in scleromyxedema is unknown. Since pulmonary hypertension presumably occurs in these patients due to disease progression and development of additional conditions, treatment of the underlying plasma cell dyscrasia and connective tissue disorder may improve pulmonary hypertension symptoms.

CASE PRESENTATION

An elderly patient with scleromyxedema developed pulmonary hypertension refractory to vasodilator and diuretic therapy and subsequently multiple myeloma that responded to a combination therapy of bortezomib, cyclophosphamide, and dexamethasone treatment.

CONCLUSIONS

Treatment of the underlying disease(s) that contributed to pulmonary hypertension development with anti-neoplastic agents like bortezomib may improve cardiopulmonary symptoms secondary to reducing abnormal blood cell counts and paraprotein levels.

Drug-associated pulmonary arterial hypertension

INTRODUCTION

While pulmonary arterial hypertension remains an uncommon diagnosis, various therapeutic agents are recognized as important associations. These agents are typically categorized into "definite", "likely", "possible", or "unlikely" to cause pulmonary arterial hypertension, based on the strength of evidence.

OBJECTIVE

This review will focus on those therapeutic agents where there is sufficient literature to adequately comment on the role of the agent in the pathogenesis of pulmonary arterial hypertension.

METHODS

A systematic search was conducted using PubMed covering the period September 1970- 2017. The search term utilized was "drug induced pulmonary hypertension". This resulted in the identification of 853 peer-reviewed articles including case reports. Each paper was then reviewed by the authors for its relevance. The majority of these papers (599) were excluded as they related to systemic hypertension, chronic obstructive pulmonary disease, human immunodeficiency virus, pulmonary fibrosis, alternate differential diagnosis, treatment, basic science, adverse effects of treatment, and pulmonary hypertension secondary to pulmonary embolism. Agents affecting serotonin metabolism (and related anorexigens): Anorexigens, such as aminorex, fenfluramine, benfluorex, phenylpropanolamine, and dexfenfluramine were the first class of medications recognized to cause pulmonary arterial hypertension. Although most of these medications have now been withdrawn worldwide, they remain important not only from a historical perspective, but because their impact on serotonin metabolism remains relevant. Selective serotonin reuptake inhibitors, tryptophan, and lithium, which affect serotonin metabolism, have also been implicated in the development of pulmonary arterial hypertension. Interferon and related medications: Interferon alfa and sofosbuvir have been linked to the development of pulmonary arterial hypertension in patients with other risk factors, such as human immunodeficiency virus co-infection. Antiviral therapies: Sofosbuvir has been associated with two cases of pulmonary artery hypertension in patients with multiple risk factors for its development. Its role in pathogenesis remains unclear. Small molecule tyrosine kinase inhibitors: Small molecule tyrosine kinase inhibitors represent a relatively new class of medications. Of these dasatinib has the strongest evidence in drug-induced pulmonary arterial hypertension, considered a recognized cause. Nilotinib, ponatinib, carfilzomib, and ruxolitinib are newer agents, which paradoxically have been linked to both cause and treatment for pulmonary arterial hypertension. Monoclonal antibodies and immune regulating medications: Several case reports have linked some monoclonal antibodies and immune modulating therapies to pulmonary arterial hypertension. There are no large series documenting an increased prevalence of pulmonary arterial hypertension complicating these agents; nonetheless, trastuzumab emtansine, rituximab, bevacizumab, cyclosporine, and leflunomide have all been implicated in case reports. Opioids and substances of abuse: Buprenorphine and cocaine have been identified as potential causes of pulmonary arterial hypertension. The mechanism by which this occurs is unclear. Tramadol has been demonstrated to cause severe, transient, and reversible pulmonary hypertension. Chemotherapeutic agents: Alkylating and alkylating-like agents, such as bleomycin, cyclophosphamide, and mitomycin have increased the risk of pulmonary veno-occlusive disease, which may be clinically indistinct from pulmonary arterial hypertension. Thalidomide and paclitaxel have also been implicated as potential causes. Miscellaneous medications: Protamine appears to be able to cause acute, reversible pulmonary hypertension when bound to heparin. Amiodarone is also capable of causing pulmonary hypertension by way of recognized side effects.

CONCLUSIONS

Pulmonary arterial hypertension remains a rare diagnosis, with drug-induced causes even more uncommon, accounting for only 10.5% of cases in large registry series. Despite several agents being implicated in the development of PAH, the supportive evidence is typically limited, based on case series and observational data. Furthermore, even in the drugs with relatively strong associations, factors that predispose an individual to PAH have yet to be elucidated.