Riociguat in patients with sickle cell disease and hypertension or proteinuria (STERIO-SCD): a randomised, double-blind, placebo controlled, phase 1-2 trial

BACKGROUND

Although nitric oxide based therapeutics have been shown in preclinical models to reduce vaso-occlusive events and improve cardiovascular function, a clinical trial of a phosphodiesterase 5 inhibitor increased rates of admission to hospital for pain. We aimed to examine if riociguat, a direct stimulator of the nitric oxide receptor soluble guanylate cyclase, causes similar increases in vaso-occlusive events.

METHODS

This was a phase 1-2, randomised, double blind, placebo-controlled trial. Eligible patients were 18 years or older, had confirmed sickle cell disease documented by haemoglobin electrophoresis or HPLC fractionation (haemoglobin SS, SC, Sβ-thalassemia, SD, or SO-Arab), and stage 1 hypertension or proteinuria. Participants were randomly assigned 1:1 to receive either riociguat or matching placebo via a web-based system to maintain allocation concealment. Both treatments were administered orally starting at 1·0 mg three times a day up to 2·5 mg three times a day (highest tolerated dose) for 12 weeks. Dose escalation by 0·5 mg was considered every 2 weeks if systolic blood pressure was greater than 95 mm Hg and the participant had no signs of hypotension; otherwise, the last dose was maintained. The primary outcome was the proportion of participants who had at least one adjudicated treatment-emergent serious adverse event. The analysis was performed by the intention-to-treat. This trial is registered with ClinicalTrials.gov (NCT02633397) and was completed.

FINDINGS

Between April 11, 2017, and Dec 31, 2021, 165 participants were screened and consented to be enrolled into the study. Of these, 130 participants were randomly assigned to either riociguat (n=66) or placebo (n=64). The proportion of participants with at least one treatment-emergent serious adverse event was 22·7% (n=15) in the riociguat group and 31·3% (n=20) in the placebo group (difference -8·5% [90% CI -21·4 to 4·5]; p=0·19). A similar pattern emerged in other key safety outcomes, sickle cell related vaso-occlusive events (16·7 [n=11] vs 21·9% [n=14]; difference -5·2% [-17·2 to 6·5]; p=0·42), mean pain severity (3·18 vs 3·32; adjusted mean difference -0·14 [-0·70 to 0·42]; p=0·69), and pain interference (3·15 vs 3·12; 0·04 [-0·62 to 0·69]; p=0·93) at 12 weeks were similar between groups. Regarding the key clinical efficacy endpoints, participants taking riociguat had a blood pressure of -8·20 mm Hg (-10·48 to -5·91) compared with -1·24 (-3·58 to 1·10) in those taking placebo (-6·96 mm Hg (90% CI -10·22 to -3·69; p<0·001).

INTERPRETATION

Riociguat was safe and had a significant haemodynamic effect on systemic blood pressure. The results of this study provide measures of effect and variability that will inform power calculations for future trials.

FUNDING

Bayer Pharmaceuticals.

Enhanced IgG immune response to COVID-19 vaccination in patients with sickle cell disease

Patients with sickle cell disease (SCD) are considered to be immunocompromised, yet data on the antibody response to SARS-CoV-2 vaccination in SCD is limited. We investigated anti-SARS-CoV-2 IgG titres and overall neutralizing activity in 201 adults with SCD and demographically matched non-SCD controls. Unexpectedly, patients with SCD generate a more robust and durable COVID-19 vaccine IgG response compared to matched controls, though the neutralizing activity remained similar across both cohorts. These findings suggest that patients with SCD achieve a similar antibody response following COVID-19 vaccination compared to the general population, with implications for optimal vaccination strategies for patients with SCD.

Presentations and outcomes among sickle cell disease patients with COVID-19 at a large southern healthcare system

OBJECTIVES

Compared with the general population, patients with sickle cell disease (SCD) typically have substantially reduced life expectancies. It is unclear whether SCD patients who acquire COVID-19 have higher rates of complications and mortality than the general population. We sought to elucidate COVID-19 presentation and outcomes in patients with SCD.

METHODS

Using retrospective chart review, we evaluated demographic characteristics, presenting symptoms, chest imaging findings, blood transfusion requirements, need for mechanical ventilation or pressor support, medication administration (including remdesivir and dexamethasone), and survival among individuals with SCD hospitalized with COVID-19 from March 2020 to December 2021.

RESULTS

Among 72 SCD patients, increased pain was the most common presenting symptom followed by cough, fever, and dyspnea. Thirty-seven (44%) received simple transfusion and 14 (17%) underwent exchange transfusion. Lung imaging findings suggestive of COVID-19 were observed in 27 (37%) patients; 21 (29%) patients were treated with remdesivir and 26 (35%) received dexamethasone. Three patients (4%) required mechanical ventilation and pressor support; all three died from COVID complications.

CONCLUSIONS

Pain is the most common presenting symptom in SCD patients with COVID-19. We observed a mortality rate higher than that among the general population among patients who required mechanical ventilation and pressor support.

Sickle Cell Disease and Kidney

Sickle cell disease causes several kidney manifestations. They include defects in urine concentration, impaired handling of potassium and hydrogen ion, albuminuria, acute kidney injury, and chronic kidney disease to name a few. Glomerular hyperfiltration, tubular hyperfunctioning, endothelial damage from repeated sickling and vaso-occlusive episodes, and iron-induced proinflammatory changes in the glomerular mesangium and tubulointerstitium are some of the mechanisms of kidney damage. Albuminuria is one of the most and common clinical features of kidney disease and progresses with age. Kidney disease in patients with sickle cell is associated with increased mortality. Annual screening for proteinuria starting at age 10 years and limiting the use of nonsteroidal anti-inflammatory agents and the use of angiotensin-converting enzyme inhibitors may help in early detection and delaying the progression of kidney disease. Adequate hydration, angiotensin-converting enzyme inhibitors, and adequate control of sickle cell are the main stay of treatment for albuminuria. The hemoglobin goal for patients with sickle cell nephropathy is lesser (10 g/dL) than that for patients with chronic kidney disease due to other causes given that a higher hemoglobin level increases viscosity and the risk of precipitating vaso-occlusive episodes. A multidisciplinary approach is recommended for managing patients with sickle cell and kidney diseases.

Catastrophic Neurological Complications in 2 Patients With Sickle Cell Disease and COVID-19

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection is commonly associated with neurological complications. Patients with sickle cell disease are at increased risk of developing neurologic complications throughout their lifetimes and often have underlying cardiopulmonary comorbidities that may predispose them to poor outcomes during serious infections. In this case series, we describe 2 patients with sickle cell disease who developed devastating neurologic complications following SARS-CoV-2 infection, which ultimately led to brain edema and death. We highlight the unusual manifestations of coronavirus disease 2019 in patients with sickle cell disease and address the risk of these patients to develop catastrophic neurologic injury due to COVID-19, if not recognized promptly.

Impact of sickle cell disease on patients' daily lives, symptoms reported, and disease management strategies: Results from the international Sickle Cell World Assessment Survey (SWAY)

Sickle cell disease (SCD) is a genetic disorder, characterized by hemolytic anemia and vaso‐occlusive crises (VOCs). Data on the global SCD impact on quality of life (QoL) from the patient viewpoint are limited. The international Sickle Cell World Assessment Survey (SWAY) aimed to provide insights into patient‐reported impact of SCD on QoL. This cross‐sectional survey of SCD patients enrolled by healthcare professionals and advocacy groups assessed disease impact on daily life, education and work, symptoms, treatment goals, and disease management. Opinions were captured using a Likert scale of 1‐7 for some questions; 5‐7 indicated “high severity/impact.” Two thousand one hundred and forty five patients (mean age 24.7 years [standard deviation (SD) = 13.1], 39% ≤18 years, 52% female) were surveyed from 16 countries (six geographical regions). A substantial proportion of patients reported that SCD caused a high negative impact on emotions (60%) and school achievement (51%) and a reduction in work hours (53%). A mean of 5.3 VOCs (SD = 6.8) was reported over the 12 months prior to survey (median 3.0 [interquartile range 2.0‐6.0]); 24% were managed at home and 76% required healthcare services. Other than VOCs, fatigue was the most commonly reported symptom in the month before survey (65%), graded “high severity” by 67% of patients. Depression and anxiety were reported by 39% and 38% of patients, respectively. The most common patient treatment goal was improving QoL (55%). Findings from SWAY reaffirm that SCD confers a significant burden on patients, epitomized by the high impact on patientsʼ QoL and emotional wellbeing, and the high prevalence of self‐reported VOCs and other symptoms.

Extreme hyperbilirubinemia: An indicator of morbidity and mortality in sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is a disorder that results in increased hospitalizations and higher mortality. Advances in management have resulted in increases in life expectancy and led to increasing awareness of sickle cell hepatopathy (SCH). However, its impact in patients on the natural history and outcomes of SCD is not known. Our study aims to describe the prevalence of extreme hyperbilirubinemia (EH), one form of SCH, its effect on morbidity and mortality, and correlations between sickle cell genotype and SCH type. We hypothesize that EH is associated with higher morbidity and mortality.

AIM

To investigate the effects of EH on morbidity and mortality among patients with SCD.

METHODS

This retrospective cohort study was performed using a database of patients with SCD treated at Grady Memorial Hospital between May 2004 and January 2017. Patients with EH (defined as total bilirubin above 13.0 mg/dL) were identified. A control group was identified from the same database with patients with total serum bilirubin ≤ 5.0 mg/dL. Electronic medical records were used to extract demographic information, laboratory values, radiology results, current medications, need for transfusions and mortality data. Two samples T-test, chi-squared test and Fisher’s exact test were then used to compare the parameters between the two groups.

RESULTS

Out of the database, fifty-seven charts were found of patients with bilirubin > 13 mg/dL. Prevalence of severe SCH as defined by EH was 4.8% (57/1172). There were no demographic differences between patients with and without EH. Significant genotypic differences existed between the two groups, with hemoglobin SS SCD being much higher in the EH group (P < 0.001). Patients with severe EH had a significant elevations in alanine aminotransferase (157.0 ± 266.2 IU/L vs 19.8 ± 21.3 IU/L, P < 0.001), aspartate aminotransferase (256.5 ± 485.9 U/L vs 28.2 ± 14.7 U/L, P < 0.001) and alkaline phosphatase (218.0 ± 176.2 IU/L vs 85.9 ± 68.4 IU/L, P < 0.001). Patients with EH had significantly higher degree of end organ failure measured with quick Sequential Organ Failure Assessment scores (0.42 ± 0.68 vs 0.01 ± 0.12, P < 0.001), increased need for blood products (63% vs 5%, P < 0.001), and exchange transfusions (10.5% vs 1.3%, P = 0.022).

CONCLUSION

Among patients with SCD, elevated levels of total bilirubin are rare, but indicative of elevated morbidity, mortality, and need for blood transfusions. Large differences in sickle cell genotype also exist, but the significance of this is unknown.

Challenges in the treatment and prevention of delayed hemolytic transfusion reactions with hyperhemolysis in sickle cell disease patients

BACKGROUND

Delayed hemolytic transfusion reactions (DHTRs) are serious complications of RBC transfusion that can occur in previously alloimmunized patients. Patients who require episodic transfusions during heightened inflammatory states, such as patients with sickle cell disease (SCD), are particularly prone to alloimmunization and developing DHTRs with hyperhemolysis. While efforts to mitigate these hemolytic episodes via immunosuppressive drugs can be employed, the relative efficacy of various treatment options remains incompletely understood.

CASE REPORTS

In this study, we explored five patients with SCD and multiple RBC alloantibodies who received various forms of immunosuppressive therapy in an attempt to prevent or treat severe DHTRs.

RESULTS

The clinical course for these five patients provides insight into the difficulty of effectively treating and preventing DHTRs in patients with SCD with currently available immunosuppressive therapies.

CONCLUSION

Based on our experience, and the current literature, it is difficult to predict the potential impact of various immunosuppressive therapies when seeking to prevent or treat DHTRs. Future mechanistic studies are needed to identify the optimal treatment options for DHTRs in the presence or absence of distinct alloantibodies in patients with SCD.

Transfusion-transmitted malaria masquerading as sickle cell crisis with multisystem organ failure

BACKGROUND

Fever accompanying vaso-occlusive crisis is a common presentation in patients with sickle cell disease (SCD) and carries a broad differential diagnosis. Here, we report a case of transfusion-transmitted malaria in a patient with SCD presenting with acute vaso-occlusive crisis and rapidly decompensating to multisystem organ failure (MSOF).

CASE REPORT

An 18-year-old African American male with SCD was admitted after multiple days of fever and severe generalized body pain. He received monthly blood transfusions as stroke prophylaxis. A source of infection was not readily identified, but treatment was initiated with continuous intravenous fluids and empiric antibiotics. The patient developed acute renal failure, acute hypoxic respiratory failure, and shock. He underwent red blood cell (RBC) exchange transfusion followed by therapeutic plasma exchange and continuous veno-venous hemodialysis. A manual peripheral blood smear revealed intraerythrocytic inclusions suggestive of Plasmodium, and molecular studies confirmed Plasmodium falciparum infection. Intravenous artesunate was given daily for 1 week. A look-back investigation involving two hospitals, multiple blood suppliers, and state and federal public health departments identified the source of malaria as a unit of RBCs transfused 2 weeks prior to admission.

CONCLUSIONS

Clinical suspicion for transfusion-related adverse events, including hemolytic transfusion reactions and transfusion-transmitted infections, should be high in typically and atypically immunocompromised patient populations (like SCD), especially those on chronic transfusion protocols. Manual blood smear review aids in the evaluation of patients with SCD presenting with severe vaso-occlusive crisis and MSOF and can alert clinicians to the need for initiating aggressive therapy like RBC exchange and artesunate therapy.

Outcomes of Newly Diagnosed Chronic Phase Chronic Myeloid Leukemia Following an Elective Switch From Second-Generation Tyrosine Kinase Inhibitor to Imatinib

The second-generation tyrosine kinase inhibitors (TKIs) (2G-TKIs) dasatinib (DAS) and nilotinib (NIL) yield faster responses in newly diagnosed chronic phase (CP) chronic myeloid leukemia (CML) as compared with imatinib (IM); however, long-term safety of these agents is a growing concern. We identified 20 patients with CP-CML diagnosed between August 2013 and October 2016 who initiated 2G-TKIs and were then switched after optimal response at 3 months to IM. Second-generation TKIs initiated were DAS (n = 15), NIL (n = 3), or both sequentially due to intolerance (n = 1). One other patient initiated therapy with ponatinib on trial. Response was assessed by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) for BCR-ABL1 levels every 3 months and in patients with qRT-PCR values less than 10% at 3 months, IM was started at 400 mg/d. IM was well tolerated except in 2 patients who required dose-reduction and discontinuation due to grade 2 skin rash (1) and grade 2 anxiety (1). After initiation of IM therapy, the BCR-ABL1 qRT-PCR levels trended down as expected. At 12 months 16 (84.2%) of 19 evaluable patients showed a 3 log (major molecular remission) or better reduction in their PCR levels. In conclusion, this retrospective analysis shows that IM can be safely and effectively administered following optimal response to 2G-TKIs. A prospective trial exploring this approach is currently enrolling and will be needed to confirm the safety and efficacy of this therapeutic approach.

Predicting early blast transformation in chronic-phase chronic myeloid leukemia: is immunophenotyping the missing link?

BACKGROUND

Flow cytometry (FC) is a commonly requested test in the workup of leukocytosis in community practices. The role of FC in chronic-phase chronic myeloid leukemia (CP-CML) is unknown. We hypothesized that finding aberrant cells with FC in CP-CML may predict early blast-phase (BP) transformation.

METHODS

Results for FC performed at the time of diagnosis for adult and pediatric patients with CP-CML who were referred to our institution were reviewed, and they were correlated with outcomes.

RESULTS

FC was performed at the time of diagnosis for 110 of 233 patients (47%) with CP-CML. Aberrant populations, representing a median of 2% (range, 0.3%-15%), were detected with FC in 30% of patients (33 of 110): 2 of these 33 patients expressed lymphoid markers, and 31 expressed aberrant myeloid markers. Patients received imatinib (85%), dasatinib (12%), or nilotinib (3%) as their first-line treatment. With a median follow-up of 43 months (range, 2-113 months), chronic myeloid leukemia transformed to BP in 5 of the 33 patients. The 2 patients with lymphoid markers and the 3 of 31 patients with aberrant myeloid markers experienced a transformation to lymphoid BP at a median of 11 months (range, 4-72 months) after the initiation of tyrosine kinase inhibitor therapy. Although both cases with detectable lymphoid markers rapidly progressed to lymphoid BP, the positive predictive value of BP transformation by the detection of myeloid aberrant cells with FC was only 10% (3 of 31).

CONCLUSIONS

In contrast to aberrant myeloid markers, the detection of lymphoid markers by FC at the time of the diagnosis of CP-CML appears to be associated with early progression to lymphoid BP.

Incidence and geographic distribution of adult acute leukemia in the state of Georgia

OBJECTIVE

We investigated an apparent increase in acute lymphoblastic leukemia (ALL) referrals from northern Georgia to a tertiary care center located in Atlanta.

METHODS

Cases reported to the Georgia Comprehensive Cancer Registry and the national Surveillance Epidemiology and End Results cancer registry between 1999 and 2008 were analyzed. Age-adjusted incidence rates were calculated for all of the counties and public health regions and were compared with national rates calculated using Surveillance Epidemiology and End Results 17 data. Cases of adult acute myeloid leukemia served as controls.

RESULTS

Age-adjusted incidence rates of adult ALL (0.8/100,000) and acute myeloid leukemia (4.6/100,000) were comparable to the national rates (0.9 and 5.2, respectively). The age-adjusted incidence rate of ALL in northern Georgia was 1.1 (95% confidence interval 0.8-1.5) and was not affected by race.

CONCLUSIONS

The observed increase in cases of ALL at our tertiary center results from a referral pattern rather than heterogeneous distribution of adult ALL across Georgia.

Advances in hematopoietic stem cell transplantation in chronic myeloid leukemia

Treatment of chronic myeloid leukemia (CML) has evolved dramatically with the development of tyrosine kinase inhibitors (TKIs). This past decade also witnessed major advances in the field of allogeneic hematopoietic stem cell transplantation (alloHSCT) that led to better patients' outcomes. Progress in the exploitation of alternative sources of stem cells, development of novel conditioning regimens, discovery of innovative graft-versus-host prophylactic strategies, and advances in supportive care as well as positioning of alloHSCT in the overall management of CML are discussed in this article.

Update on optimal management of acute myeloid leukemia

Acute myeloid leukemia (AML) represents a malignant accumulation of immature myeloid cells in the marrow, presenting with impaired hematopoiesis and its attendant complications, including bleeding, infection, and organ infiltration. Chromosomal abnormalities remain the most powerful predictors of AML prognosis and help to identify a subgroup with favorable prognosis. However, the majority of AML patients who are not in the favorable category succumb to the disease. Therefore, better efforts to identify those patients who may benefit from more aggressive and investigational therapeutic approaches are needed. Newer molecular markers aim at better characterizing the large group of intermediate-risk patients and to identify newer targets for therapy. A group that has seen little improvement over the years is the older AML group, usually defined as age ≥ 60. Efforts to develop less intensive but equally efficacious therapy for this vulnerable population are underway.

Bosutinib: a SRC-ABL tyrosine kinase inhibitor for treatment of chronic myeloid leukemia

Bosutinib is one of five tyrosine kinase inhibitors commercially available in the United States for the treatment of chronic myeloid leukemia. This review of bosutinib summarizes the mode of action, pharmacokinetics, efficacy and safety data, as well as the patient-focused perspective through quality-of-life data. Bosutinib has shown considerable and sustained efficacy in chronic myeloid leukemia, especially in the chronic phase, with resistance or intolerance to prior tyrosine kinase inhibitors. Bosutinib has distinct but manageable adverse events. In the absence of T315I and V299L mutations, there are no absolute contraindications for the use of bosutinib in this patient population.

Venous access catheter-related thrombosis in patients with cancer

Patients with cancer are at high risk for developing venous thromboembolism (VTE), and the presence of a central venous catheter (CVC) further increases this risk. CVC-related VTE has serious implications related to the loss of vascular access, development of pulmonary embolism, recurrent VTE, infections and post-thrombotic syndrome. The pathogenesis of CVC-related VTE is complex and multifactorial, with risk factors associated with the catheter, the vessel selected for insertion and the underlying cancer as well as the anti-cancer therapy. Clinical presentation of CVC-related VTEs is often non-specific, and ultrasonography is the most commonly used radiological diagnostic test. Management of CVC-related VTE in patients with cancer requires a balance between the need for venous access, the risk of VTE recurrence and the risk of bleeding from treatment-induced thrombocytopenia. Effective VTE prophylaxis methods have yet to be defined. Ongoing studies are evaluating the role of newer oral antithrombotic agents and alternative interventional strategies for the prevention and treatment of CVC-related VTE in patients with cancer.

Relation between iron-overload indices, cardiac echo-Doppler, and biochemical markers in thalassemia intermedia

Cardiovascular impairment is a major cause of morbidity and mortality in patients with thalassemia intermedia. In this study, echocardiographic assessment of left heart condition was performed in patients with thalassemia intermedia, and its relation to hematologic variables--amino terminal pro-brain natriuretic peptide (NT-proBNP), ferritin, hemoglobin--and liver iron concentration (LIC) was investigated. Echocardiographic assessment was performed using pulse-wave Doppler and tissue Doppler imaging. Data from 74 patients with thalassemia intermedia--35 men, 39 women, mean age 26.5 years (8 to 63)--were randomly selected and evaluated. Blood samples were collected for NT-proBNP levels in a random subgroup of 19 patients. Mean baseline values were hemoglobin 8.4 g/dl (4.9 to 13.1), serum ferritin 902.6 ng/ml (15 to 4,140), LIC 9.0 mg Fe/g (0.5 to 32.1), and NT-proBNP 113.5 pg/ml (16.4 to 371). Correlation between LIC and pulmonary artery systolic pressure was significant, suggesting that iron loading in the liver is indicative of cardiovascular sequelae. NT-proBNP was significantly correlated with the ratio of the left ventricular early rapid filling wave to early diastolic velocity at the mitral annulus (r = 0.50, p = 0.04) and hemoglobin (r = -0.49, p = 0.03), but not with other characteristics assessed. In conclusion, this study has highlighted the importance of using tissue Doppler imaging rather than pulse-wave Doppler to characterize left ventricular diastolic dysfunction in patients with thalassemia intermedia. Demonstration of the correlation of LIC and pulmonary artery systolic pressure independent of left ventricular filling pressures supports our hypothesis that left ventricular diastolic dysfunction does not contribute to the increased pulmonary artery systolic pressure in patients with thalassemia intermedia.