Importance:For patients with idiopathic pulmonary fibrosis (IPF), cough impairs quality of life; effective treatments for IPF-associated cough are needed. Objective:To determine if nalbuphine extended release (ER), a κ opioid receptor agonist and μ-opioid receptor antagonist, decreases cough compared with placebo in patients with IPF-associated cough. Design, Setting, and Participants:In this randomized, double-blind, placebo-controlled phase 2b trial conducted at 52 sites in 10 countries, patients with IPF, chronic cough for at least 8 weeks, and a Cough Severity Numerical Rating Scale (0, no cough; 10, worst possible cough) score of 4 or higher were enrolled from February 2024 to February 2025, with last follow-up in April 2025. Statistical analyses were conducted from May to August 2025. Intervention:Patients were randomized 1:1:1:1 to receive nalbuphine ER at doses of 27 mg, 54 mg, or 108 mg or placebo twice daily for 6 weeks. Main Outcomes and Measures:The primary outcome was the relative change from baseline in 24-hour cough frequency (coughs/h), measured with a digital cough monitor, for nalbuphine ER compared with placebo at week 6. The key secondary outcome was the relative change from baseline in the patient-reported cough frequency (Evaluating Respiratory Symptoms in IPF cough subscale; scores range from 0-4, lower scores indicate lesser cough frequency) at week 6. Results:Of the 223 patients screened, 165 were randomized (42, 43, 40, and 40 to receive nalbuphine ER 27 mg, 54 mg, and 108 mg, and placebo, respectively) and 160 were included in the primary analysis (median age, 71 [range, 51-85] years; 28.5% female). The baseline mean (SD) cough count was 28.3 (27.4) coughs/h. In the nalbuphine ER 27 mg, 54 mg, and 108 mg twice-daily groups, the mean relative decrease in the cough count and the absolute decrease in coughs/h were 47.9% (from 24.6 to 11.9; P = .008), 53.4% (from 28.0 to 14.9; P < .001), and 60.2% (from 31.5 to 11.9; P < .001), respectively, compared with placebo (16.9%; from 29.4 to 28.1 coughs/h). For the key secondary outcome of patient-reported cough frequency at week 6, the relative and absolute changes were -31.4% (from 2.3 to 1.5; P = .14), -40.6% (from 2.6 to 1.4; P = .004), and -40.2% (from 2.4 to 1.4; P < .005) in the 27-mg, 54-mg, and 108-mg groups, respectively, compared with -21.9% (from 2.6 to 1.9) with placebo. Conclusions and Relevance:For patients with IPF-associated chronic cough, all 3 doses of nalbuphine ER reduced objective cough frequency and the 2 higher doses improved patient-reported cough frequency at 6 weeks. Trial Registration:ClinicalTrials.gov Identifier: NCT05964335.

BACKGROUND:Acoramidis achieves near-complete (≥90%) transthyretin stabilization and is approved to reduce cardiovascular-related mortality and hospitalization in transthyretin amyloid cardiomyopathy. Its effects on kidney function are not well characterized. METHODS:Data from randomized phase 2 (N=49) and phase 3 (N=632) studies in transthyretin amyloid cardiomyopathy were included. The estimated glomerular filtration rate (eGFR) slope was generated using a linear spline mixed-effects model. The urinary albumin-to-creatinine ratio was measured longitudinally. Relationships between changes in kidney function and clinical outcomes were explored using Cox proportional hazards models. RESULTS:Acoramidis initiation resulted in a modest acute dip in eGFR that was dose-dependent, reversible, and not associated with adverse kidney-related events. At Day 28, the mean (±SE) dip in eGFR from baseline with acoramidis was 8.5±0.48 mL/min per 1.73 m2; the placebo-corrected reduction in the urinary albumin-to-creatinine ratio was 15.5% (95% CI, 0.4%-28.4%; P=0.044). The rate of decline in kidney function (chronic eGFR slope) was significantly improved with acoramidis versus placebo (-1.01 versus -3.48 mL/min per 1.73 m2 per year; P<0.001), and the reduction in the urinary albumin-to-creatinine ratio was sustained (13.7% [95% CI, 1.7%-24.2%]; P=0.026) over time. Concomitant tafamidis use did not influence the chronic eGFR slope in either arm. Comparing acoramidis versus placebo subgroups with acute eGFR dips ≥ the median (4.89 mL/min per 1.73 m2) favored acoramidis for all-cause mortality or cardiovascular-related hospitalization (hazard ratio, 0.42 [95% CI, 0.22-0.78]; P=0.006; P interaction=0.043) and cardiovascular-related hospitalization (hazard ratio, 0.34 [95% CI, 0.17-0.66]; P=0.002, P interaction=0.025). Within the placebo arm, eGFR dips portended worse outcomes. CONCLUSIONS:Acoramidis initiation resulted in an acute dip in eGFR and reductions in both the chronic eGFR slope and urinary albumin-to-creatinine ratio versus placebo without adverse kidney-related events. Acoramidis effects on kidney function may be mediated through direct kidney-protective hemodynamic effects. Importantly, the acute dip in eGFR was associated with a reduced risk of adverse clinical outcomes within the first year. REGISTRATION:URL: https://www.clinicaltrials.gov; Unique identifiers: NCT03458130, NCT03536767, NCT03860935, NCT04988386.

For patients with idiopathic pulmonary fibrosis (IPF), cough impairs quality of life; effective treatments for IPF-associated cough are needed. To determine if nalbuphine extended release (ER), a κ opioid receptor agonist and μ-opioid receptor antagonist, decreases cough compared with placebo in patients with IPF-associated cough. In this randomized, double-blind, placebo-controlled phase 2b trial conducted at 52 sites in 10 countries, patients with IPF, chronic cough for at least 8 weeks, and a Cough Severity Numerical Rating Scale (0, no cough; 10, worst possible cough) score of 4 or higher were enrolled from February 2024 to February 2025, with last follow-up in April 2025. Statistical analyses were conducted from May to August 2025. Patients were randomized 1:1:1:1 to receive nalbuphine ER at doses of 27 mg, 54 mg, or 108 mg or placebo twice daily for 6 weeks. The primary outcome was the relative change from baseline in 24-hour cough frequency (coughs/h), measured with a digital cough monitor, for nalbuphine ER compared with placebo at week 6. The key secondary outcome was the relative change from baseline in the patient-reported cough frequency (Evaluating Respiratory Symptoms in IPF cough subscale; scores range from 0-4, lower scores indicate lesser cough frequency) at week 6. Of the 223 patients screened, 165 were randomized (42, 43, 40, and 40 to receive nalbuphine ER 27 mg, 54 mg, and 108 mg, and placebo, respectively) and 160 were included in the primary analysis (median age, 71 [range, 51-85] years; 28.5% female). The baseline mean (SD) cough count was 28.3 (27.4) coughs/h. In the nalbuphine ER 27 mg, 54 mg, and 108 mg twice-daily groups, the mean relative decrease in the cough count and the absolute decrease in coughs/h were 47.9% (from 24.6 to 11.9; P = .008), 53.4% (from 28.0 to 14.9; P < .001), and 60.2% (from 31.5 to 11.9; P < .001), respectively, compared with placebo (16.9%; from 29.4 to 28.1 coughs/h). For the key secondary outcome of patient-reported cough frequency at week 6, the relative and absolute changes were −31.4% (from 2.3 to 1.5; P = .14), −40.6% (from 2.6 to 1.4; P = .004), and −40.2% (from 2.4 to 1.4; P < .005) in the 27-mg, 54-mg, and 108-mg groups, respectively, compared with –21.9% (from 2.6 to 1.9) with placebo. For patients with IPF-associated chronic cough, all 3 doses of nalbuphine ER reduced objective cough frequency and the 2 higher doses improved patient-reported cough frequency at 6 weeks. ClinicalTrials.gov Identifier: NCT05964335

PURPOSE:Phosphate binders (PB) are integral to hyperphosphatemia management in patients with end-stage kidney disease. PB efficacy is adversely affected by nonadherence and limited phosphate-binding capacity relative to dietary intake. Oxylanthanum carbonate is an investigational novel nanotechnology product that combines lanthanum, which has the highest binding capacity of available PBs, with a smaller pill size that is swallowed with water rather than chewed. This study's objective was to demonstrate the pharmacodynamic equivalence of orally administered oxylanthanum carbonate to lanthanum carbonate (LC) in healthy subjects. METHODS:In this phase one, single-center, randomized, open-label study, healthy subjects were treated with oxylanthanum carbonate swallowable tablets 1000 mg three times/day and LC chewable tablets 1000 mg three times/day in a two-way crossover design. The primary pharmacodynamic variable was the least squares mean (LSM) change in urinary phosphate excretion from baseline to the evaluation period (Days 1-4 of treatment). FINDINGS:A total of 80 subjects were randomized and 75 received all doses. The LSM change in urinary phosphate excretion from Baseline to the Evaluation (Treatment) Period was similar for both oxylanthanum carbonate (-320.4 mg/day [90% CI: -349.7, -291.0]) and LC (-324.0 mg/day [90% CI: -353.3, -294.7]); the between-group LSM difference was 3.6 [90% CI: -37.8, 45.1] mg/day. Both drugs were well tolerated with an equal incidence of adverse events. IMPLICATIONS:Thus, oxylanthanum carbonate was bioequivalent to LC in healthy subjects and well tolerated. Oral oxylanthanum carbonate may provide an option for patients with chronic kidney disease and hyperphosphatemia for whom chewing tablets is disliked, inconvenient, or difficult. CLINICAL TRIAL REGISTRATION NUMBER:NCT06218290.

STUDY QUESTION What is the efficacy and safety of long-term treatment (up to 2 years) with relugolix combination therapy (CT) in women with moderate to severe endometriosis-associated pain? SUMMARY ANSWER For up to 2 years, treatment with relugolix CT improved menstrual and non-menstrual pain, dyspareunia, and function in women with endometriosis; after an initial decline of <1%, the mean bone mineral density (BMD) remained stable with continued treatment. WHAT IS KNOWN ALREADY Endometriosis is a chronic condition characterized by symptoms of dysmenorrhea, non-menstrual pelvic pain (NMPP), and dyspareunia, which have a substantial impact on the lives of affected women, their partners, and families. SPIRIT 1 and 2 were phase 3, randomized, double-blind, placebo-controlled studies of once-daily relugolix CT (relugolix 40 mg, oestradiol 1 mg, norethisterone acetate 0.5 mg) in premenopausal women (age 18-50 years) with endometriosis and moderate-to-severe dysmenorrhea and NMPP. These trials demonstrated a significant improvement of dysmenorrhea, NMPP, and dyspareunia in women treated with relugolix CT, with minimal decline (<1%) in BMD versus placebo at 24 weeks. STUDY DESIGN, SIZE, DURATION Patients participating in this open-label, single-arm, long-term extension (LTE) study of the 24-week SPIRIT pivotal studies (SPIRIT 1 and 2) received up to an additional 80 weeks of once-daily oral relugolix CT treatment between May 2018 and January 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS Premenopausal women with confirmed endometriosis and moderate to severe dysmenorrhea and NMPP who completed the 24-week pivotal studies (SPIRIT 1 and 2 trials; ) and who met all entry criteria were eligible to enrol. Two-year results were analysed by treatment group based on original randomization in pivotal studies: relugolix CT, delayed relugolix CT (relugolix 40 mg monotherapy for 12 weeks, followed by relugolix CT), or placebo -> relugolix CT (placebo for 24 weeks followed by relugolix CT). The primary endpoints of the LTE study were the proportion of dysmenorrhea and NMPP responders at Week 52 and Week 104/end-of-treatment (EOT). A responder was a participant who achieved a predefined, clinically meaningful reduction from baseline in Numerical Rating Scale (NRS) scores (0 = no pain, 10 = worst pain imaginable) for the specific pain type with no increase in analgesic use. The predefined clinically meaningful threshold for dysmenorrhea was 2.8 points and for NMPP was 2.1 points. Secondary efficacy endpoints included change from baseline in Endometriosis Health Profile-30 (EHP-30) pain domain scores, a measure of the effects of endometriosis-associated pain on daily activities (function), NRS scores for dysmenorrhea, NMPP, dyspareunia, and overall pelvic pain, and analgesic/opioid use. Safety endpoints included adverse events and changes in BMD. MAIN RESULTS AND THE ROLE OF CHANCE Of 1261 randomized patients, 1044 completed the pivotal studies, 802 enrolled in the LTE, 681 completed 52 weeks of treatment, and 501 completed 104 weeks of treatment. Demographics and baseline characteristics of the extension population were consistent with those of the original randomized population. Among patients randomized to relugolix CT at pivotal study baseline who continued in the LTE (N = 277), sustained improvements in endometriosis-associated pain were demonstrated through 104 weeks. The proportion of responders at Week 104/EOT for dysmenorrhea and NMPP was 84.8% and 75.8%, respectively. Decreases in dyspareunia and improvement in function assessed by EHP-30 pain domain were also sustained over 2 years. At Week 104/EOT, 91% of patients were opioid-free and 75% of patients were analgesic-free. Relugolix CT over 104 weeks was well tolerated with a safety profile consistent with that observed over the first 24 weeks. After initial least squares mean BMD loss <1% at Week 24, BMD plateaued at Week 36 and was sustained for the duration of 104 weeks of treatment. Efficacy and safety results were generally consistent in women in the placebo -> relugolix CT and delayed relugolix CT groups. LIMITATIONS, REASONS FOR CAUTION The study was conducted as an open-label study without a control group over the 80 weeks of the extension period. Of the 802 patients who were enrolled in this LTE study, 681 patients (84.9%) and 501 patients (62.5%) of patients completed 52 and 104 weeks of treatment, respectively. In addition, there currently are no comparative data to other hormonal medications. Finally, a third (37.4%) of the study population terminated participation early. WIDER IMPLICATIONS OF THE FINDINGS In conclusion, relugolix CT offers an additional option to help address an important unmet clinical need for effective, safe, and well-tolerated medical treatments for endometriosis that can be used longer-term, reducing the need for opioids and improving quality of life. The findings from this study may help support the care of women with endometriosis seeking longer-term effective medical management of their symptoms. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by Myovant Sciences GmbH (now Sumitomo Pharma Switzerland GmbH). C.M.B. reports fees from Myovant, grants from Bayer Healthcare, fees from ObsEva, and Chair of ESHRE Endometriosis Guideline Group (all funds went to the University of Oxford); N.P.J. reports personal fees from Myovant Sciences, during the conduct of the study, personal fees from Guerbet, personal fees from Organon, personal fees from Roche Diagnostics; S.A.-S. reports personal fees from Myovant Sciences, personal fees from Bayer, personal fees from Abbvie, personal fees from UpToDate; J.S.P., and R.B.W. are employees and shareholders of Myovant Sciences; J.C.A.F. and S.J.I. are shareholders of Myovant Sciences (but at time of publicaion are no longer employess of Myovant Sciences); M.S.A. and K.W. have no conflicts to declare; V.M. is a consultant to Myovant; L.C.G. reports personal fees from Myovant Sciences, Inc and Bayer. The authors did not receive compensation for manuscript writing, review, and revision. TRIAL REGISTRATION NUMBER NCT03654274.

Background: Reducing overweight and obesity has been a longstanding focus of public health messaging and physician-patient interactions. Clinical guidelines by major public health organizations describe both overweight and obesity as risk factors for mortality and other health conditions. Accordingly, a majority of primary care physicians believe that overweight BMI (even without obesity) strongly increases mortality risk.Main points: The current evidence base suggests that although both obese BMI and underweight BMI are consistently associated with increased all-cause mortality, overweight BMI (without obesity) is not meaningfully associated with increased mortality. In fact, a number of studies suggest modest protective, rather than detrimental, associations of overweight BMI with all-cause mortality. Given this current evidence base, clinical guidelines and physician perceptions substantially overstate all-cause mortality risks associated with the range of BMIs classified as “overweight” but not “obese”. Discrepancies between evidence and communication regarding mortality raise the question of whether similar discrepancies exist for other health outcomes.Conclusions: Health communication that inaccurately conveys current evidence may do more harm than good; this applies to communication from health authorities to health practitioners as well as to communication from health practitioners to individual patients. We give three recommendations to better align health communication with the current evidence. First, recommendations to the public and health practitioners should distinguish overweight from obese BMI, and at this time should not describe overweight BMI as a risk factor for all-cause mortality. Second, primary care physicians’ widespread misconceptions about overweight BMI should be rectified. Third, the evidence basis for other potential risks or benefits of overweight BMI should be rigorously examined and incorporated appropriately into health communication.

Introduction: Low serum bicarbonate at a single point in time is associated with accelerated kidney decline in patients with chronic kidney disease (CKD). We modeled how changes in serum bicarbonate over time affect incidence of adverse kidney outcomes. Methods: We analyzed data from Optum's deidentified Integrated Claims-Clinical data set of US patients (2007-2019) with >= 1 year of prior medical record data, CKD stages G3 to G5, and metabolic acidosis (i.e., index serum bicarbonate 12 to <22 mmol/l). The primary predictor of interest was the change in serum bicarbonate, evaluated at each postindex outpatient serum bicarbonate test as a time-dependent continuous variable. The primary outcome was a composite of either a >= 40% decline in estimated glomerular filtration rate (eGFR) from index or evidence of dialysis or transplantation, evaluated using Cox proportional hazards models. Results: A total of 24,384 patients were included in the cohort with median follow-up of 3.7 years. A withinpatient increase in serum bicarbonate over time was associated with a lower risk of the composite kidney outcome. The unadjusted hazard ratio (HR) per 1-mmol/l increase in serum bicarbonate was 0.911 (95% confidence interval [CI]: 0.905-0.917; P < 0.001). After adjustment for baseline eGFR and serum bicarbonate, the time-adjusted effect of baseline eGFR and other covariates, the HR per 1-mmol/l increase in serum bicarbonate was largely unchanged (0.916 [95% CI: 0.910-0.922; P < 0.001]). Conclusion: In a real-world population of US patients with CKD and metabolic acidosis, a within-patient increase in serum bicarbonate over time independent of changes in eGFR, was associated with a lower risk of CKD progression. 2023 International Society of Nephrology. Published by Elsevier Inc. This is an open access article under the CC BY

Introduction: The Kidney Failure Risk Equations (KFRE) are accurate and validated to predict the risk of kidney failure in individuals with chronic kidney disease (CKD), but their potential to predict health care costs in the US health care system is unknown. We assessed the association of kidney failure risk from the 4-variable and 8-variable 2-year KFRE models with monthly health care costs in US patients with CKD stages G3 and G4. Methods: This was an ancillary study to a larger observational, retrospective cohort study examining the association between serum bicarbonate and adverse kidney outcomes. Monthly medical costs were calculated from individual health care insurance claims. Generalized linear regression models were used to examine the association of KFRE score with health care costs. Results: A total of 1721 patients qualified for the study (1475 and 246 with CKD stages G3 and G4, respectively). For 8-variable KFRE, each 1% (absolute) increase in risk was associated with 13.5% (P < 0.001) and 4.1% (P < 0.001) higher monthly costs for patients with CKD stage G3 and G4, respectively. For 4-variable KFRE, a 1% increase in risk was associated with 6.7% (P= 0.016) and 2.9% (P= 0.014) increase in monthly costs for patients with CKD stage G3 and G4, respectively. Conclusion: Higher risks of kidney failure as predicted by the 4-variable or 8-variable KFRE were associ-ated with higher 2-year medical costs for patients with CKD stages G3 and G4. The KFRE may be a useful tool to anticipate medical costs and target cost-reducing interventions for patients at risk of kidney failure.

Given current evidence, clinical guidelines consider obesity (body mass index [BMI] ≥ 30), but not overweight (BMI 25–29.9), to be a risk factor for all-cause mortality. Two prominent meta-analyses in general populations have estimated associations of different BMI categories with all-cause mortality; these meta-analyses reported modest associations in opposite directions for the overweight category. Another meta-analysis suggested that in older adults, being overweight is associated with modestly reduced mortality. Given that primary care physicians (PCPs) frequently advise patients on BMI, we used matched clinical vignettes to assess PCPs’ perceptions of the direction and strength of the overweight-mortality association (n=192). We found that a large majority of PCPs (90%) perceive that being overweight increases all-cause mortality risk, contrasting with findings of clinical guidelines’ authors. PCPs typically estimate a strength of association that substantially exceeds current empirical estimates.

Background: Frailty is common in patients with chronic kidney disease (CKD), as is its physical component, phenotypic frailty, and each contributes to CKD-related disability and are associated with increased mortality. Chronic kidney disease has been described as a model of premature aging and its phenotypic frailty shares features with that which has been better characterized for aging. Summary: Decreased skeletal muscle function contributes to the phenotypic frailty of CKD and aging and potentially remediable metabolic derangements appear to mediate both. Key Messages: Metabolic derangements of skeletal muscle dysfunction shared by CKD-related and aging-related phenotypic frailty offer potential research avenues to help identify additional preventive and treatment strategies. Those derangements distinctive for CKD provide potential treatment targets for the kidney care community to enhance the quality and quantity of life for patients with CKD.

WHAT IS THIS SUMMARY ABOUT?:This is a summary of research studies (known as clinical trials) called SPIRIT 1 and SPIRIT 2. The SPIRIT 1 and SPIRIT 2 studies compared how well a medicine called relugolix combination therapy worked in relieving pain in women with moderate to severe endometriosis compared to a placebo, a pill with no active medication. Endometriosis occurs when tissue similar to what normally lines the uterus grows in other places, such as the ovaries, fallopian tubes, and bowels. WHAT WERE THE RESULTS?:Researchers looked at 1261 adult women with moderate to severe endometriosis. Randomly, 420 (33%) of these women were assigned to relugolix combination therapy, 420 (33%) were assigned to delayed relugolix combination therapy (relugolix alone first and then relugolix combination therapy for the remainder of the study), and 421 (33%) were assigned to placebo. The SPIRIT 1 and SPIRIT 2 studies showed that more women taking relugolix combination therapy (75% from SPIRIT 1 and 75% from SPIRIT 2) for 24 weeks had both less pelvic or groin pain during menstrual periods from endometriosis and no need for more pain medicines than women who took placebo (27% from SPIRIT 1 and 30% from SPIRIT 2). The SPIRIT 1 and SPIRIT 2 studies also showed that more women taking relugolix combination therapy (59% from SPIRIT 1 and 66% from SPIRIT 2) for 24 weeks had both less pelvic or groin pain between menstrual periods from endometriosis and no need for more pain medicines than women who took placebo (40% from SPIRIT 1 and 43% from SPIRIT 2). Women taking relugolix combination therapy had less pelvic or groin pain during and between menstrual periods within 4 weeks of starting the medicine. The most common side effects were headaches, the common cold, and hot flushes or feeling hot among women taking relugolix combination therapy, delayed relugolix combination therapy, and placebo. Relugolix combination therapy was considered safe for those with no major medical problems. Women taking relugolix combination therapy had little to no loss of bone mineral density (a way of knowing how strong bones are) after 24 weeks of treatment. WHAT DO THE RESULTS OF THESE STUDIES TELL US?:Women with moderate to severe endometriosis taking relugolix combination therapy had much less pain from endometriosis than women taking placebo. Clinical Trial Registration: NCT03204318 (SPIRIT-1); NCT03204331 (SPIRIT-2) (ClinicalTrials.gov).

Rationale & Objective: Identification of treatable risk factors for kidney allograft failure is necessary to improve graft longevity. Metabolic acidosis with either low serum bicarbonate or normal serum bicarbonate (eubicarbonatemic metabolic acidosis) is implicated in native kidney disease progression but its effects in kidney transplant recipients are unclear.Study Design: Retrospective cohort study.Setting & Participants: An Integrated Claims Clinical dataset of US patients with chronic kidney disease (estimated glomerular filtration rates <60 mL/min/1.73 m2) and serum bicarbonate data were used to generate a cohort of kidney transplant recipients with data from >= 1 year before and after transplantation. Primary Predictor: The primary independent variable was a change in serum bicarbonate from baseline.Outcomes: The primary outcomes were graft failure and all-cause mortality. The secondary outcomes were major adverse cardiac events and all-cause hospitalization.Analytical Approach: We used adjusted time dependent Cox proportional hazards models to assess the risk of graft failure, all-cause mortality, major adverse cardiac events, and time to first hospitalization.Results: In this US community-based cohort of 1,915 kidney transplant recipients with a median follow-up of w2.5 years, each 1-mEq/L increase in serum bicarbonate was associated with significantly lower hazard of graft loss, death, major adverse cardiac events, and hospitalization by 10%, 8%, 4%, and 8%, respectively. Limitations: Possible residual confounding.Conclusions: In a US community-based population of kidney transplant recipients, even small incremental increases in serum bicarbonate (1 mEq/L) were significantly associated with reduced hazard of graft loss, all-cause mortality, cardiovascular events, and hospitalization. Interventional trials evaluating the potential benefits of treating metabolic acidosis in kidney transplant recipients are warranted.

ABSTRACT Background Whether treating metabolic acidosis slows progression of chronic kidney disease (CKD) has not been established. Veverimer is a novel hydrochloric acid binder that removes acid from the gastrointestinal tract leading to an increase in serum bicarbonate; it is being developed to treat metabolic acidosis with the goal of slowing progression of CKD. Methods The VALOR-CKD trial is an international, randomized, multicenter, double-blind, placebo-controlled study designed to evaluate the effect of once-daily veverimer on kidney disease progression in patients with metabolic acidosis and CKD. Eligibility criteria include a serum bicarbonate in the range of 12–20 mmol/L and an estimated glomerular filtration rate (eGFR) of 20–40 mL/min/1.73 m2. The primary outcome is kidney disease progression defined as the development of end-stage kidney disease, a sustained decline in eGFR of >40% from baseline or death due to kidney failure. Key secondary endpoints include effects on physical function. Results Between December 2018 and December 2021, 1480 participants were randomized. The mean age at baseline was 65.1 years and 42% of the patients were female. The mean baseline eGFR was 29.1 mL/min/1.73 m2 and mean serum bicarbonate was 17.5 mmol/L. The median urine albumin-to-creatinine ratio at screening was 201 mg/g and the median 5-year predicted risk of kidney failure was 32%. Diabetes and hypertension were present in 56% and 98% of participants, respectively. Conclusions VALOR-CKD has recruited a large population of people with metabolic acidosis at high risk for CKD progression to determine the effects of veverimer on the risk of progressive loss of kidney function.

ABSTRACT Background Epidemiological studies demonstrate an association between kidney stones and risk of chronic kidney disease (CKD) and CKD progression. Metabolic acidosis, as a consequence of CKD, results in a reduced urine pH which promotes the formation of some types of kidney stones and inhibits the formation of others. While metabolic acidosis is a risk factor for CKD progression, the association of serum bicarbonate with risk of incident kidney stones is not well understood. Methods We used an Integrated Claims-Clinical dataset of US patients to generate a cohort of patients with non-dialysis-dependent CKD with two serum bicarbonate values of 12 to <22 mmol/L (metabolic acidosis) or 22 to <30 mmol/L (normal serum bicarbonate). Primary exposure variables were baseline serum bicarbonate and change in serum bicarbonate over time. Cox proportional hazards models evaluated time to first occurrence of kidney stones during a median 3.2-year follow-up. Results A total of 142 884 patients qualified for the study cohort. Patients with metabolic acidosis experienced post–index date kidney stones at greater frequency than patients with normal serum bicarbonate at the index date (12.0% vs 9.5%, P < .0001). Both lower baseline serum bicarbonate [hazard ratio (HR) 1.047; 95% confidence interval (CI) 1.036–1.057] and decreasing serum bicarbonate over time (HR 1.034; 95% CI 1.026–1.043) were associated with increased risk of kidney stone development. Conclusions Metabolic acidosis was associated with a higher incidence of kidney stones and shorter time to incident stone formation in patients with CKD. Future studies may investigate the role of correcting metabolic acidosis to prevent stone formation.

Abstract Aims Higher body mass index (BMI) is associated with higher bone mass and bone serves as a buffer during the development of metabolic acidosis. The authors sought to examine the relationship between BMI and metabolic acidosis in patients with chronic kidney disease (CKD). Materials and Methods The study utilized a large US longitudinal data repository including over 103 million patients from healthcare provider organizations to evaluate the relationship between the exposure variable (BMI) and the prevalence and incidence of metabolic acidosis among patients with estimated glomerular filtration rate <60 ml/min/1.73 m2. Incident metabolic acidosis was identified at the first of two consecutive post‐index serum bicarbonate values, 10–365 days apart, between 12 and <22 mEq/L in patients with normal index serum bicarbonate. Cox proportional hazard models were adjusted for multiple variables including demographics, comorbidities, income, education, and kidney function. Results 103,766 patients qualified for this study; 6472 (6.2%) had metabolic acidosis at index. An inverse association between BMI category and metabolic acidosis was observed for both baseline (prevalence) and new‐onset (incidence) metabolic acidosis. Compared to BMI category of 18.5 to <25 kg/m2, each category of incrementally higher BMI was associated with a decreasing risk of incident metabolic acidosis; the adjusted hazard ratios (95% confidence interval) were 0.866 (0.824–0.911), 0.770 (0.729–0.813), 0.664 (0.622–0.709), and 0.612 (0.571–0.655) for BMI 25 to <30, 30 to <35, 35 to <40, and 40+ kg/m2, respectively. Conclusions Among patients with CKD, an incremental increase in BMI was inversely associated with both the prevalence and incidence of metabolic acidosis. These associations suggest that increased body weight may protect against the development of metabolic acidosis, a risk factor for progressive loss of kidney function.

Rationale & Objective: Metabolic acidosis is a risk factor for progression of chronic kidney disease (CKD), but little is known about its effect on health care costs and resource utilization. We describe the associations between metabolic acidosis, adverse kidney outcomes, and health care costs in patients with CKD stages G3-G5 and not receiving dialysis.Study Design: Retrospective cohort study.Setting & Participants: An integrated claims -clinical data set of US patients with CKD stages G3-G5, with serum bicarbonate values of 12 to <22 mEq/L (metabolic acidosis group) or 22 to 29 mEq/L (normal serum bicarbonate level group).Predictor: The primary exposure variable was the baseline serum bicarbonate level. Outcomes: The primary clinical outcome was the composite of all-cause mortality, maintenance dialysis, kidney transplant, or a decline in the estimated glomerular filtration rate of >= 40% (DD40). The primary cost outcome was all-cause predicted per-patient per-year cost, assessed over a 2-year outcome period. Analytical Approach: Logistic and generalized linear regression models, adjusted for key covariates such as age, sex, race, kidney function, comorbid-ities, and pharmacy insurance coverage, were used to assess serum bicarbonate levels as a predictor of DD40 and health care costs, respectively.Results: 51,558 patients qualified. The metabolic acidosis group experienced higher rates of DD40 (48.3% vs. 16.7%, P < 0.001) and higher all-cause yearly costs ($65,172 vs. $24,681, P < 0.001). Two-year adjusted odds ratio of DD40 per 1-mEq/L increase in serum bicarbonate levels was 0.873 (95% CI, 0.866-0.879); the parameter estimate (+/- SE) for costs was -0.070 +/- 0.0075 (P < 0.001).Limitations: Possible residual confounding.Conclusions: Patients with CKD and metabolic acidosis had higher costs and rates of adverse kidney outcomes compared with patients with normal serum bicarbonate levels. Each 1-mEq/L increase in serum bicarbonate levels was associated with a 13% decrease in 2-year DD40 events and a 7% decrease in per-patient per-year cost.

Introduction: The percentage of patients initiating dialysis at an estimated glomerular filtration rate (eGFR) ≤9 mL/min/1.73 m2 decreased between 2000 and 2018 in the USA. Clinical practice guidelines recommend basing the decision to initiate dialysis primarily on uremic signs and symptoms rather than on a particular level of kidney function. However, what signs and symptoms currently practicing nephrologists consider “uremic,” how they weigh eGFR and other factors in the decision to initiate dialysis have not been reported. Methods: The study was an online survey of 255 US nephrologists, conducted between August and October 2021. Results: Nearly half of respondents (49.8%) had an absolute lower eGFR (8.4 [95% CI: 7.6, 9.2] mL/min/1.73 m2) at which they would initiate dialysis in an asymptomatic patient. The top 5 symptoms that would trigger a recommendation to initiate dialysis were loss of appetite/nausea/vomiting (17%), low eGFR (10%), shortness of breath (10%), declining physical ability/function (9%), and generalized weakness (9%). Poor nutritional status and physical function decline were considered very important in the decision to initiate dialysis by 64% and 55% of respondents, respectively. Nephrologists surveyed significantly shortened the time to dialysis initiation in response to declining physical function in an otherwise asymptomatic (hypothetical) patient. Conclusions: Nearly half of nephrologists sometimes based their decision to initiate dialysis on eGFR alone. The eGFR threshold at which they did so was lower than has been examined in randomized controlled trials of dialysis initiation. Initiatives designed to safely delay dialysis through aggressive medical management could focus on modifiable factors that are the most important drivers of the decision to initiate dialysis.

ABSTRACT Background The risk of adverse geriatric outcomes such as falls and fractures is high among patients with chronic kidney disease (CKD). Metabolic acidosis is associated with protein catabolism and bone loss in experimental animal and human studies. We sought to quantify the independent association of metabolic acidosis with adverse muscle, bone and functional outcomes in a large US community-based cohort. Methods The Optum's de-identified Integrated Claims-Clinical dataset of US patients (2007–2017) was used to generate a cohort of patients with nondialysis-dependent CKD who had estimated glomerular filtration rate >10 to <60 mL/min/1.73 m2 and two serum bicarbonate values 12 to <22 mmol/L or 22–29 mmol/L. The primary outcomes were failure to thrive, protein-calorie malnutrition, and fall or fracture. Cox proportional hazards models were used for the primary outcomes for up to 10 years, while logistic regression models were used at 2 years. Results A total of 51 558 patients qualified for the study, with a median [Interquartile Range (IQR)] follow-up time of 4.2 (2.5–5.8) years. Over a ≤10-year period, for each 1 mmol/L increase in serum bicarbonate, the hazard ratios (adjusted for age, sex, race, estimated glomerular filtration rate, serum albumin, hemoglobin, diabetes and cardiovascular comorbidities) for failure to thrive, protein-calorie malnutrition and fall or fracture were 0.91 [95% confidence interval (CI): 0.90–0.92], 0.91 (95% CI: 0.90–0.92) and 0.95 (95% CI: 0.95–0.96), all P < 0.001, respectively. Conclusions The presence and severity of metabolic acidosis was a significant, independent risk factor for failure to thrive, protein-calorie malnutrition and fall or fracture in this large community cohort of patients with stage 3–5 CKD.