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Red cell transfusion thresholds in outpatients with myelodysplastic syndromes: Results of a pilot randomized trial RBC-ENHANCE
Buckstein, R., Callum, J., Prica, A., Bowen, D., Wells, R. A., Leber, B., Heddle, N., Chodirker, L., Cheung, M., Mozessohn, L., et al
Transfusion. 2024
Abstract
BACKGROUND The optimal hemoglobin (Hb) threshold for red blood cell transfusions in adult patients with myelodysplastic syndromes (MDS) has not been defined. STUDY DESIGN AND METHODS We conducted a pilot randomized multi-center study of two transfusion algorithms (liberal, to maintain Hb 110-120 g/L, transfuse 2 units if Hb < 105 g/L and 1 unit if Hb 105-110 g/L vs. restrictive, 85-105 g/L, transfuse 2 units when Hgb < 85 g/L). Primary objectives were 70% compliance in maintaining the q2 week hemoglobin within the targeted range and the achievement of a 15 g/L difference in pre-transfusion Hb. Secondary outcomes included measures of quality of life (QOL), iron studies and safety. RESULTS Twenty-eight patients were randomized between February 2015-2020, 13 to the restrictive arm and 15 to the liberal arm in three tertiary care centers. The compliance was 66% and 45% and the mean pre-transfusion Hb thresholds were 86 (standard deviation [SD] 8) and 98 g/L (SD 10) in the restrictive and liberal arms, (mean difference 11.8 g/L, p < .0001), respectively. Patients in the liberal arm experienced a mean of 3.4 (SD 2.6) more transfusion visits and received a mean of 5.3 (SD 5.5) more units of blood during the 12-week study. Ferritin increased by 1043 (SD 1516) IU/L and 148 (SD 1319) IU/L in the liberal and restrictive arms, respectively. Selected QOL scores were superior pre-transfusion and more patients achieved clinically important improvements in the liberal arm compared with the restrictive arm for selected symptoms and function domains. CONCLUSION The results establish that policies for transfusion support can be delivered in practice at multiple hospitals, but further research is required to understand the full clinical effects and safety of liberal transfusion policies in MDS outpatients.
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The role of preoperative transfusion in sickle cell disease, a systematic review and meta-analysis
Abdu, Y., Rahhal, A., Ahmed, K., Adli, N., Abdou, M., Ali, E. A. H., Al-Kindi, S., Al Rasheed, M., Altooq, J., Bougmiza, I., et al
Blood reviews. 2024;:101183
Abstract
This systematic review and meta-analysis aimed to provide guidance on preoperative blood transfusion strategies for patients with sickle cell disease (SCD). We included all randomized controlled and observational studies exploring the clinical outcomes of preoperative blood transfusion among patients with SCD compared to the conservative transfusion strategy until 14/09/2022. Sixteen studies involving 3486 participants were analysed. The findings revealed a significantly higher bleeding rate in patients who received preoperative transfusion than those who followed a conservative strategy (RR = 4.32, 95% CI 1.75-10.68, P = 0.002, I2 = 0%). However, the two strategies had no significant differences in other clinical outcomes, such as acute chest syndrome, painful crisis, fever, neurological complications, thrombosis, ICU admission, and mortality. It is important to note that all the included studies had a moderate risk of bias. Preoperative transfusion in SCD was associated with a higher bleeding risk but a similar risk in other outcomes compared to conservative strategies. Notably, the increased bleeding risk observed seldom had clinical significance. We recommend individualizing management strategies, considering the overall positive impact of transfusions in reducing complications. Further high-quality studies are needed to refine recommendations.
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Preoperative Transfusion in Sickle Cell Disease Children Undergoing Adenotonsillectomy
Kanotra, S., Muller, S. H., Kanotra, J., Gardner, R., Kanotra, S. P.
Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India. 2023;75(2):227-235
Abstract
OBJECTIVE To perform a systematic review and meta-analysis comparing two pre-operative transfusion regimens (conservative versus aggressive) in children with sickle cell disease(SCD) undergoing adenotonsillectomy in terms of post-operative complications, complications related to SCD and transfusion related complications. DATA SOURCES AND REVIEW METHODS A literature review was performed through PubMed, EMBASE, Cochrane, and Ovid databases using the following phrases: (Adenotonsillectomy OR Tonsillectomy) AND (Sickle Cell Disease OR Sickle Cell Trait). Using predetermined inclusion and exclusion criteria, seven articles were selected for systemic review and two control trials were included in meta-analysis. RESULTS Out of a total of 3,146 results, seven articles were selected for review and two controlled trials were included in the meta-analysis. There was no statistically significant difference in the rate of primary and secondary hemorrhage between the aggressive and conservative transfusion regimens (RR = 3.1, CI = 0.84-11.4, p-value = 0.089). The rate of sickle cell disease related complications including vaso-occlusive crisis and acute chest syndrome was also not statistically significant between the two transfusion groups (RR = 1.4, CI = 0.7-2.8, p-value = 0.339). Even though, the transfusion related complications did not reach statistical significance, there was a higher complication rate in the group receiving aggressive blood transfusion. CONCLUSION In SCD children undergoing adenotonsillectomy, an aggressive transfusion regimen that focuses on reducing the Hemoglobin S ratio to below 30% has not been shown to be more effective in reducing post-operative complications when compared to a conservative transfusion regimen. Therefore, it is reasonable to utilize a conservative transfusion regimen, thereby reducing the transfusion-associated risks.
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Evidence-based interventions for reducing sickle cell disease-associated morbidity and mortality in sub-Saharan Africa: A scoping review
Arji, E. E., Eze, U. J., Ezenwaka, G. O., Kennedy, N.
SAGE open medicine. 2023;11:20503121231197866
Abstract
OBJECTIVE Sickle cell disease is a lifelong illness affecting millions of people globally, but predominantly burdensome in sub-Saharan Africa, where most affected children do not live to adulthood, despite available evidence-based interventions that reduce the disease burden in high-income countries. METHOD We reviewed studies evaluating evidence-based interventions that decrease sickle cell disease-related morbidity and mortality among children living in sub-Saharan Africa. We used the Joanna Briggs scoping review methodological framework and grouped identified evidence-based interventions into preventative pharmacotherapeutic agents, newborn screening and comprehensive healthcare, disease-modifying agents, nutritional supplementation, systemic treatment, supportive agents and patient/carer/population education. RESULTS We included 36 studies: 18 randomized controlled trials, 11 observational studies, 5 before-and-after studies and 2 economic evaluation studies, with most of the studies performed in West African countries. Included studies suggest evidence-based interventions effectively to reduce the common morbidities associated with sickle cell disease such as stroke, vaso-occlusive crisis, acute chest syndrome, severe anaemia and malaria infection. Evidence-based interventions also improve survival among study participants. Specifically, our review shows hydroxyurea increases haemoglobin and foetal haemoglobin levels, a finding with practical implications given the challenges with blood transfusion in this setting. The feasibility of implementing individual interventions is hampered by challenges such as affordability, accessibility and the availability of financial and human resources. CONCLUSION Our review suggests that regular use of low-dose hydroxyurea therapy, sulphadoxine-pyrimethamine chemoprophylaxis, L-arginine and Omega-3 fatty acid supplementation and establishment of specialist stand-alone sickle cell clinics could reduce the sickle cell disease-associated morbidity and mortality in sub-Saharan Africa countries.
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Pegcetacoplan controls hemolysis in complement inhibitor-naive patients with paroxysmal nocturnal hemoglobinuria
Wong RSM, Navarro-Cabrera JR, Comia NS, Goh YT, Idrobo H, Kongkabpan D, Gómez-Almaguer D, Al-Adhami M, Ajayi T, Alvarenga P, et al
Blood advances. 2023
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Editor's Choice
Abstract
Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disease characterized by complement-mediated hemolysis. Pegcetacoplan is the first C3-targeted therapy approved for adults with PNH (United States), adults with PNH with inadequate response to or intolerance of a C5 inhibitor (Australia), and adults with anemia despite C5-targeted therapy for 3 months (European Union). PRINCE was a phase 3, randomized, multicenter, open-label, controlled study to evaluate efficacy and safety of pegcetacoplan versus control (supportive care only; eg, blood transfusions, corticosteroids, and supplements) in complement inhibitor-naive patients with PNH. Eligible adults receiving supportive care only for PNH were randomized and stratified based on their number of transfusions (<4, ≥4) 12 months before screening. Patients received pegcetacoplan 1080 mg subcutaneously twice weekly or continued supportive care (control) for 26 weeks. Coprimary endpoints were hemoglobin stabilization (avoidance of >1-g/dL decrease in hemoglobin levels without transfusions) from baseline through week 26 and lactate dehydrogenase (LDH) change at week 26. Overall, 53 patients received pegcetacoplan (n=35) or control (n=18). Pegcetacoplan was superior to control for hemoglobin stabilization (pegcetacoplan, 85.7%; control, 0; difference, 73.1% [95% CI: 57.2, 89.0]; P <0.0001) and change from baseline in LDH (least-square mean change: pegcetacoplan, -1870.5 U/L; control -400.1 U/L; difference, -1470.4 U/L [95% CI: -2113.4, -827.3]; P <0.0001). Pegcetacoplan was well tolerated. No pegcetacoplan-related adverse events were serious, and no new safety signals observed. Pegcetacoplan rapidly and significantly stabilized hemoglobin and reduced LDH in complement inhibitor-naive patients and had a favorable safety profile. This trial was registered at www.clinicaltrials.gov as #NCT04085601.
PICO Summary
Population
Adult patients with paroxysmal nocturnal haemoglobinuria enrolled in the PRINCE trial conducted in 22 centres in Hong Kong, Malaysia, Philippines, Singapore, Thailand, Colombia, Mexico and Peru (n= 53).
Intervention
Subcutaneous infusions of pegcetacoplan (pegcetacoplan group, n= 35).
Comparison
Supportive care including transfusions, anticoagulants, corticosteroids, and supplements (control group, n= 18).
Outcome
Pegcetacoplan was superior to control for haemoglobin stabilization (pegcetacoplan, 85.7%; control, 0; difference, 73.1%, 95% CI [57.2, 89.0]) and change from baseline in lactate dehydrogenase, (least-square mean change: pegcetacoplan, -1870.5 U/L; control -400.1 U/L; difference, -1470.4 U/L, 95% CI [-2113.4, -827.3]). Pegcetacoplan was well tolerated. No pegcetacoplan-related adverse events were serious, and no new safety signals were observed.
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Interventions for chronic kidney disease in people with sickle cell disease
Roy, N. B., Carpenter, A., Dale-Harris, I., Dorée, C., Estcourt, L. J.
The Cochrane database of systematic reviews. 2023;8(8):Cd012380
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Editor's Choice
Abstract
BACKGROUND Sickle cell disease (SCD), one of the commonest severe monogenic disorders, is caused by the inheritance of two abnormal haemoglobin (beta-globin) genes. SCD can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Kidney disease is a frequent and potentially severe complication in people with SCD. Chronic kidney disease (CKD) is defined as abnormalities of kidney structure or function present for more than three months. Sickle cell nephropathy refers to the spectrum of kidney complications in SCD. Glomerular damage is a cause of microalbuminuria and can develop at an early age in children with SCD, with increased prevalence in adulthood. In people with sickle cell nephropathy, outcomes are poor as a result of the progression to proteinuria and chronic kidney insufficiency. Up to 12% of people who develop sickle cell nephropathy will develop end-stage renal disease. This is an update of a review first published in 2017. OBJECTIVES To assess the effectiveness of any intervention for preventing or reducing kidney complications or chronic kidney disease in people with sickle cell disease. Possible interventions include red blood cell transfusions, hydroxyurea, and angiotensin-converting enzyme inhibitors (ACEIs), either alone or in combination. SEARCH METHODS We searched for relevant trials in the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register, CENTRAL, MEDLINE, Embase, seven other databases, and two other trials registers. SELECTION CRITERIA Randomised controlled trials (RCTs) comparing interventions to prevent or reduce kidney complications or CKD in people with SCD. We applied no restrictions related to outcomes examined, language, or publication status. DATA COLLECTION AND ANALYSIS Two review authors independently assessed trial eligibility, extracted data, assessed the risk of bias, and assessed the certainty of the evidence (GRADE). MAIN RESULTS We included three RCTs with 385 participants. We rated the certainty of the evidence as low to very low across different outcomes according to GRADE methodology, downgrading for risk of bias concerns, indirectness, and imprecision. Hydroxyurea versus placebo One RCT published in 2011 compared hydroxyurea to placebo in 193 children aged nine to 18 months. We are unsure if hydroxyurea compared to placebo reduces or prevents progression of kidney disease assessed by change in glomerular filtration rate (mean difference (MD) 0.58 mL/min /1.73 m(2), 95% confidence interval (CI) -14.60 to 15.76; 142 participants; very low certainty). Hydroxyurea compared to placebo may improve the ability to concentrate urine (MD 42.23 mOsm/kg, 95% CI 12.14 to 72.32; 178 participants; low certainty), and may make little or no difference to SCD-related serious adverse events, including acute chest syndrome (risk ratio (RR) 0.39, 99% CI 0.13 to 1.16; 193 participants; low certainty), painful crisis (RR 0.68, 99% CI 0.45 to 1.02; 193 participants; low certainty); and hospitalisations (RR 0.83, 99% CI 0.68 to 1.01; 193 participants; low certainty). No deaths occurred in either trial arm and the RCT did not report quality of life. Angiotensin-converting enzyme inhibitors versus placebo One RCT published in 1998 compared an ACEI (captopril) to placebo in 22 adults with normal blood pressure and microalbuminuria. We are unsure if captopril compared to placebo reduces proteinuria (MD -49.00 mg/day, 95% CI -124.10 to 26.10; 22 participants; very low certainty). We are unsure if captopril reduces or prevents kidney disease as measured by creatinine clearance; the trial authors stated that creatinine clearance remained constant over six months in both groups, but provided no comparative data (very low certainty). The RCT did not report serious adverse events, all-cause mortality, or quality of life. Angiotensin-converting enzyme inhibitors versus vitamin C One RCT published in 2020 compared an ACEI (lisinopril) with vitamin C in 170 children aged one to 18 years with normal blood pressure and microalbuminuria. It reported no data we could analyse. We are unsure if lisinopril compared to vitamin C reduces proteinuria in this population: the large drop in microalbuminuria in both arms of the trial after only one month on treatment may have been due to an overestimation of microalbuminuria at baseline rather than a true effect. The RCT did not report serious adverse events, all-cause mortality, or quality of life. AUTHORS' CONCLUSIONS We are unsure if hydroxyurea improves glomerular filtration rate or reduces hyperfiltration in children aged nine to 18 months, but it may improve their ability to concentrate urine and may make little or no difference to the incidence of acute chest syndrome, painful crises, and hospitalisations. We are unsure if ACEI compared to placebo has any effect on preventing or reducing kidney complications in adults with normal blood pressure and microalbuminuria. We are unsure if ACEI compared to vitamin C has any effect on preventing or reducing kidney complications in children with normal blood pressure and microalbuminuria. No RCTs assessed red blood cell transfusions or any combined interventions to prevent or reduce kidney complications. Due to lack of evidence, we cannot comment on the management of children aged over 18 months or adults with any known genotype of SCD. We have identified a lack of adequately designed and powered studies, although we found four ongoing trials since the last version of this review. Only one ongoing trial addresses renal function as a primary outcome in the short term, but such interventions have long-term effects. Trials of hydroxyurea, ACEIs or red blood cell transfusion in older children and adults are urgently needed to determine any effect on prevention or reduction of kidney complications in people with SCD.
PICO Summary
Population
Children and adults with sickle cell disease (3 randomised controlled trials, n= 385).
Intervention
Interventions to prevent or reduce kidney complications or chronic kidney disease, including: hydroxyurea, and angiotensin-converting enzyme inhibitors (ACEIs), either alone or in combination.
Comparison
Placebo.
Outcome
This systematic review is an update of a review first published in 2017. The authors rated the certainty of the evidence as low to very low across different outcomes. The authors are unsure if hydroxyurea improves glomerular filtration rate or reduces hyperfiltration in children aged nine to 18 months, but it may improve their ability to concentrate urine and may make little or no difference to the incidence of acute chest syndrome, painful crises, and hospitalisations. The authors are unsure if ACEI compared to placebo has any effect on preventing or reducing kidney complications in adults with normal blood pressure and microalbuminuria. The authors are unsure if ACEI compared to vitamin C has any effect on preventing or reducing kidney complications in children with normal blood pressure and microalbuminuria.
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A pilot randomized study for optimal red cell transfusion in acute myeloid leukemia patients with intensive chemotherapy
Byun JM, Park W, Shin DY, Koh Y, Kim I, Yoon SS, Park JH, Kim H, Hong J
Blood transfusion = Trasfusione del sangue. 2023
Abstract
BACKGROUND Although blood transfusion is fundamental throughout the course of hematologic malignancies, acute myeloid leukemia (AML) patients requiring intensive chemotherapy are left at the edges of patient blood management programs because current guidelines do not have established recommendations for red blood cell (RBC) transfusion threshold in patients treated for hematological disorders with anemia and accompanied severe thrombocytopenia. To provide answers for the trigger and doses of ideal RBC transfusion in such situation, we conducted this prospective randomized trial. MATERIALS AND METHODS Newly diagnosed non-acute promyelocytic AML patients undergoing chemotherapy were considered eligible for enrollment. Patients were randomized into 4 groups using a 2 by 2 factorial design, according to the RBC transfusion trigger (hemoglobin [Hb], 7 vs 8 g/dL) and the number of units per transfusion episode (quantity, single vs double-unit). RESULTS Initially 91 patients were randomized into 4 groups, but the protocol adherence rate was 90.1%. Hb trigger did not affect the amount of RBC transfusion required during treatment. Patients receiving RBC transfusion at Hb <7 g/dL used a median of 4 units of RBC (range 0-12), and those receiving transfusion at Hb <8 g/dL also used a median of 4 units of RBC (range 0-24) (p=0.305). The number of RBC units per transfusion did not affect the total amount of RBC transfusion required during treatment. AML treatment outcomes and bleeding events did not differ across the 4 groups. DISCUSSION This study demonstrated the feasibility for restrictive RBC transfusion (Hb <7 g/dL, RBC 1 unit) in AML patients undergoing chemotherapy, regardless of chemotherapy intensity.
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The Role of Non-genetic Therapies to Reduce the Incidence of Sickle Cell Crisis: A Systematic Review
Pingili, S., Makkena, V. K., Jaramillo, A. P., Awosusi, B. L., Ayyub, J., Dabhi, K. N., Gohil, N. V., Tanveer, N., Hussein, S., Hamid, P.
Cureus. 2023;15(8):e42785
Abstract
Sickle cell anemia is a hemoglobinopathy that causes complications such as Vaso-Occlusive Crisis (VOC), stroke, priapism, Acute Chest Syndromes (ACS), and bone infarcts due to blood vessel occlusion, resulting in hypoxia, ischemia, and inflammation. Preventing these incidents improves the quality of life and lowers mortality rates in Sickle Cell Disease (SCD) patients. This systematic review aims to describe the drugs, their mechanisms of action, dosages, changes in hemoglobin parameters, decrease in VOCs, delay the time for the next VOC, decrease in the length of hospital stay, and side effects associated with these drugs. This review adheres to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) 2020 guidelines. For this review, we searched the PubMed, Google Scholar, and Cochrane databases and screened them for full free texts published in English and studied in humans in the last five years beginning in 2018. Randomized clinical trials (RCT), observational studies, meta-analyses, systemic reviews, and traditional reviews were all included in the search. According to the type of study, quality assessment tools are used, and eight papers are chosen. Full-text articles from these papers are studied, analyzed, and tabulated. We discussed seven interventions that are used to treat sickle cell disease. Voxelotor, crizanlizumab, L-glutamate, long-term blood transfusions, Zinc (Zn), Niprisan®, and Ciklavit* were found to reduce the number and severity of VOC. We discovered that VOCs containing L -glutamate reduced the length of hospitalization. Magnesium (Mg) did not affect the number and severity of VOCs. This review includes a few articles for the study. Future papers on this subject should include a large sample size and many papers. More clinical trials are required to evaluate the dosages and outcomes of using these drugs in combination to prevent VOCs.
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Extramedullary haematopoiesis in patients with transfusion dependent β-thalassaemia (TDT): a systematic review
A Subahi E, Ata F, Choudry H, Iqbal P, A AlHiyari M, T Soliman A, De Sanctis V, A Yassin M
Annals of medicine. 2022;54(1):764-774
Abstract
INTRODUCTION Around 5% of the world's population is expected to have some degree and type of thalassaemia. Beta thalassaemia (BT) occurs due to a deficient production of the beta-globin chain of haemoglobin. Extramedullary haematopoiesis (EMH) is one of the complications of BT, mainly observed in minor/intermedia subtypes. EMH is the production of blood cells outside the marrow as a compensatory response to longstanding hypoxia. Due to chronic transfusions, it is not expected in patients with beta-thalassaemia major (BTM). However, there are increasingly reported cases of EMH in BTM. The incidence of EMH in BTM is thought to be <1%. We aim to pool the available data and provide cumulative evidence on the occurrence of EMH in BTM patients. METHODS This is a systematic review of case reports, series, and retrospective studies that presented data on the occurrence of EMH in BTM patients. Data were recorded and analyzed in Microsoft Excel 2016 and SPSS 26. The protocol has been registered in PROSPERO CRD42021242943. RESULTS Data from 253 cases of EMH in BTM patients were extracted with a mean age of 35.3 years. Mean haemoglobin at presentation with EMH was 8.2 mg/dL. Lower limb weakness was the most common presenting feature (N = 23) (paraspinal EMH). Magnetic resonance imaging (MRI) was the most widely used diagnostic modality (226). Overall, blood transfusion was the commonest reported treatment (30), followed by radiotherapy (20), surgery (15), hydroxyurea (12), steroids (6), and exchange transfusion (2). An outcome was reported in 20% of patients, all recovered, except one who died as a result of nosocomial infection. CONCLUSION EMH is rare in BTM and can occur in any organ system with varied clinical features. MRI can effectively diagnose EMH, and conservative management has similar results compared to invasive treatments. Larger studies, focussing on outcomes may enhance guidelines on preventive and therapeutic strategies for managing EMH in BTM.KEY MESSAGESExtramedullary haematopoiesis is a rare complication in beta thalassaemia. Although it is more common in non-transfusion dependent thalassaemia, increasingly reported cases suggest a higher prevalence of EMH in TDT than what is known before.There are no clear guidelines on the management of EMH in TDT, with reported patients showing similar outcomes with conservative invasive treatment modalities.More extensive and preferably prospectively designed studies are required focussing on the management of EMH and its outcomes in patients with TDT to formulate evidence-based guidelines.
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Overview of current progress and challenges in diagnosis, and management of pediatric sickle cell disease in Democratic Republic of the Congo
Kasai ET, Alworong'a Opara JP, Ntokamunda Kadima J, Kalenga M, Batina Agasa S, Marini Djang'eing'a R, Boemer F
Hematology (Amsterdam, Netherlands). 2022;27(1):132-140
Abstract
OBJECTIVES Sickle cell disease (SCD) encompasses health complications, primarily affecting the hematologic system and leading to high death rates in childhood. As a rule, the World Health Organisation (WHO) stepwise gold-standard about the strategies for prevention, diagnosis, and treatment of SCD must be multidimensional. This overview aimed to highlight current advances and challenges linked to strategic issues, diagnosis, the prevalence, and treatment of pediatric cases in Sub-Saharan Africa, particularly the Democratic Republic of the Congo. METHODS We searched data on Google Scholar, Medline, PubMed, Science Direct, Scopus, and ResearchGate. RESULTS The laboratory diagnosis of SCD has progressed from conventional electrophoresis to rapid point-of-care tests that allows early neonate screening. HemoTypeSC(TM) is an affordable test for neonatal screening in DRC. The pediatric SCD prevalence in Sub-Saharan Africa lay within 1-7.7% of homozygous(SS) and 15-40% of the heterozygous(AS) forms of SCD, depending on the method used and the ethnic population tested. Various supportive management protocols for comorbidities and complications exist, but they are not standardized in the Region. CONCLUSION Notwithstanding some progress accomplished, the disease is still challenging in Sub-Saharan Africa due to limited early diagnostic testing and a lack of specific medications. There is a need for harmonizing therapeutic protocols and conducting controlled valid clinical trials.