Comparative Emergence of Maribavir and Ganciclovir Resistance in a Randomized Phase 3 Clinical Trial for Treatment of Cytomegalovirus Infection.

BACKGROUND: Among 547 patients receiving maribavir or valganciclovir for first-episode cytomegalovirus infection after hematopoietic cell transplant, the treatment response rate was 69.6% and 77.4% respectively. Development of maribavir and ganciclovir resistance was compared after receiving either drug. METHODS: Viral mutations conferring drug resistance were analyzed in plasma DNA extracts at baseline and post-treatment. RESULTS: Prior antiviral drug exposure was limited, with only 2 instances of baseline drug resistance detected. An equal number (n=241) received valganciclovir or maribavir for at least 21 days (median 55-56 days). Among them, drug resistance mutations were detected in 24 (10%) maribavir recipients at 35-125 days (median 56) after starting therapy, including in 12 of 14 who experienced a viral load rebound while on therapy. Ganciclovir resistance mutations developed in 6 (2.5%) valganciclovir recipients at 66-110 days (median 90). One maribavir recipient developed a novel UL97 gene mutation (P-loop substitution G343A) that conferred strong maribavir and ganciclovir resistance in vitro. Viral clearance was confirmed in 17 (74%) of 23 patients with emergent maribavir resistance after re-treatment with an alternative CMV antiviral drug. CONCLUSION: After 3-8 weeks of therapy, maribavir resistance emerged earlier and more frequently than ganciclovir resistance but was usually treatable using alternative therapy. CLINICAL TRIALS REGISTRATION: NCT02927067 (AURORA).

Treatment for First Cytomegalovirus Infection Post-Hematopoietic Cell Transplant in the AURORA Trial: A Multicenter, Double-Blind, Randomized, Phase 3 Trial Comparing Maribavir With Valganciclovir.

BACKGROUND: Neutropenia may limit the use of valganciclovir treatment for cytomegalovirus (CMV) infection following hematopoietic cell transplant (HCT). A phase 2 study indicated efficacy of maribavir with fewer treatment-limiting toxicities than valganciclovir. METHODS: In this multicenter, double-blind, phase 3 study, patients with first asymptomatic CMV infection post-HCT were stratified and randomized 1:1 to maribavir 400 mg twice daily or valganciclovir (dose-adjusted for renal clearance) for 8 weeks with 12 weeks of follow-up. The primary endpoint was confirmed CMV viremia clearance at week 8 (primary hypothesis of noninferiority margin of 7.0%). The key secondary endpoint was a composite of the primary endpoint with no findings of CMV tissue-invasive disease at week 8 through week 16. Treatment-emergent adverse events (TEAEs) were assessed. RESULTS: Among patients treated (273 maribavir; 274 valganciclovir), the primary endpoint of noninferiority of maribavir was not met (maribavir, 69.6%; valganciclovir, 77.4%; adjusted difference: -7.7%; 95% confidence interval [CI]: -14.98, -.36; lower limit of 95% CI of treatment difference exceeded -7.0%). At week 16, 52.7% and 48.5% of patients treated (maribavir and valganciclovir, respectively) maintained CMV viremia clearance without tissue-invasive disease (adjusted difference: 4.4%; 95% CI: -3.91, 12.76). With maribavir (vs valganciclovir), fewer patients experienced neutropenia (16.1% and 52.9%) or discontinued due to TEAEs (27.8% and 41.2%). Discontinuations were mostly due to neutropenia (maribavir, 4.0%; valganciclovir, 17.5%). CONCLUSIONS: Although noninferiority of maribavir to valganciclovir for the primary endpoint was not achieved based on the prespecified noninferiority margin, maribavir demonstrated comparable CMV viremia clearance during post-treatment follow-up, with fewer discontinuations due to neutropenia. Clinical Trials Registration. NCT02927067 [AURORA].

Guidance on the Use of Convalescent Plasma to Treat Immunocompromised Patients With Coronavirus Disease 2019.

Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) is a safe and effective treatment for COVID-19 in immunocompromised (IC) patients. IC patients have a higher risk of persistent infection, severe disease, and death from COVID-19. Despite the continued clinical use of CCP to treat IC patients, the optimal dose, frequency/schedule, and duration of CCP treatment has yet to be determined, and related best practices guidelines are lacking. A group of individuals with expertise spanning infectious diseases, virology and transfusion medicine was assembled to render an expert opinion statement pertaining to the use of CCP for IC patients. For optimal effect, CCP should be recently and locally collected to match circulating variant. CCP should be considered for the treatment of IC patients with acute and protracted COVID-19; dosage depends on clinical setting (acute vs protracted COVID-19). CCP containing high-titer severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies, retains activity against circulating SARS-CoV-2 variants, which have otherwise rendered monoclonal antibodies ineffective.

Neutralizing activity and 3-month durability of tixagevimab and cilgavimab prophylaxis against Omicron sublineages in transplant recipients.

Neutralizing antibody (nAb) responses are attenuated in solid organ transplant recipients (SOTRs) despite severe acute respiratory syndrome-coronavirus-2 vaccination. Preexposure prophylaxis (PrEP) with the antibody combination tixagevimab and cilgavimab (T+C) might augment immunoprotection, yet in vitro activity and durability against Omicron sublineages BA.4/5 in fully vaccinated SOTRs have not been delineated. Vaccinated SOTRs, who received 300 + 300 mg T+C (ie, full dose), within a prospective observational cohort submitted pre and postinjection samples between January 31, 2022, and July 6, 2022. The peak live virus nAb was measured against Omicron sublineages (BA.1, BA.2, BA.2.12.1, and BA.4), and surrogate neutralization (percent inhibition of angiotensin-converting enzyme 2 receptor binding to full length spike, validated vs live virus) was measured out to 3 months against sublineages, including BA.4/5. With live virus testing, the proportion of SOTRs with any nAb increased against BA.2 (47%-100%; P < .01), BA.2.12.1 (27%-80%; P < .01), and BA.4 (27%-93%; P < .01), but not against BA.1 (40%-33%; P = .6). The proportion of SOTRs with surrogate neutralizing inhibition against BA.5, however, fell to 15% by 3 months. Two participants developed mild severe acute respiratory syndrome-coronavirus-2 infection during follow-up. The majority of fully vaccinated SOTRs receiving T+C PrEP achieved BA.4/5 neutralization, yet nAb activity commonly waned by 3 months postinjection. It is critical to assess the optimal dose and interval of T+C PrEP to maximize protection in a changing variant climate.

Persistent SARS-CoV-2-specific immune defects in kidney transplant recipients following third mRNA vaccine dose.

Kidney transplant recipients (KTRs) show poorer response to SARS-CoV-2 mRNA vaccination, yet response patterns and mechanistic drivers following third doses are ill-defined. We administered third monovalent mRNA vaccines to n = 81 KTRs with negative or low-titer anti-receptor binding domain (RBD) antibody (n = 39 anti-RBDNEG; n = 42 anti-RBDLO), compared with healthy controls (HCs, n = 19), measuring anti-RBD, Omicron neutralization, spike-specific CD8+%, and SARS-CoV-2-reactive T cell receptor (TCR) repertoires. By day 30, 44% anti-RBDNEG remained seronegative; 5% KTRs developed BA.5 neutralization (vs 68% HCs, P < .001). Day 30 spike-specific CD8+% was negative in 91% KTRs (vs 20% HCs; P = .07), without correlation to anti-RBD (rs = 0.17). Day 30 SARS-CoV-2-reactive TCR repertoires were detected in 52% KTRs vs 74% HCs (P = .11). Spike-specific CD4+ TCR expansion was similar between KTRs and HCs, yet KTR CD8+ TCR depth was 7.6-fold lower (P = .001). Global negative response was seen in 7% KTRs, associated with high-dose MMF (P = .037); 44% showed global positive response. Of the KTRs, 16% experienced breakthrough infections, with 2 hospitalizations; prebreakthrough variant neutralization was poor. Absent neutralizing and CD8+ responses in KTRs indicate vulnerability to COVID-19 despite 3-dose mRNA vaccination. Lack of neutralization despite CD4+ expansion suggests B cell dysfunction and/or ineffective T cell help. Development of more effective KTR vaccine strategies is critical. (NCT04969263).

Patient-reported outcomes after Tixagevimab and Cilgavimab pre-exposure prophylaxis among solid organ transplant recipients: Safety, effectiveness, and perceptions of risk.

BACKGROUND: Tixagevimab and Cilgavimab (T + C) is authorized for pre-exposure prophylaxis (PrEP) against Coronavirus Disease 2019 (COVID-19) in solid organ transplant recipients (SOTRs), yet patient-reported outcomes after injection are not well described. Furthermore, changes in risk tolerance after T + C PrEP have not been reported, of interest given uncertain activity against emerging Omicron sublineages. METHODS: Within a national prospective observational study, SOTRs who reported receiving T + C were surveyed for 3 months to ascertain: (1) local and systemic reactogenicity, (2) severe adverse events with focus on cardiovascular and alloimmune complications, and (3) breakthrough COVID-19, contextualized through (4) changes in attitudes regarding COVID-19 risk and behaviors. RESULTS: At 7 days postinjection, the most common reactions were mild fatigue (29%), headache (20%), and pain at injection sites (18%). Severe adverse events were uncommon; over 3 months of follow-up, 4/392 (1%) reported acute rejection and one (.3%) reported a myocardial infarction. Breakthrough COVID-19 occurred in 9%, 16-129 days after receiving full dose (300/300 mg) T + C, including two non-ICU hospitalizations. Most surveyed SOTRs (65%) felt T + C PrEP was likely to reduce their COVID-19 risk, and 70% reported increased willingness to engage in social activities such as visiting friends. However, few felt safe to return to in-person work (20%) or cease public mask-wearing (15%). CONCLUSIONS: In this prospective study of patient-reported outcomes, T + C was well tolerated with few serious events. Several COVID-19 breakthroughs were reported, notable as most SOTRs reported changes in risk tolerance after T + C. These results aid counseling of SOTRs regarding real-world safety and effectiveness of T + C.

Progressive disseminated histoplasmosis: The experience in one non-endemic medical center.

Histoplasmosis, the most common endemic mycosis in North America, presents in a myriad of ways, spanning the spectrum from self-limiting pneumonia to progressive disseminated histoplasmosis (PDH). Toward better describing contemporary histoplasmosis syndromes, risks, and outcomes, this single-center retrospective cohort study was performed (2009-2019). The population who developed PDH was similar to that with other forms of histoplasmosis (OFH) except for higher rates of preexisting immunocompromising conditions (91.3% vs. 40%, P < .001) and a trend toward receiving more chronic immunosuppression (65.2% vs. 33.3%, P = .054) compared to those with OFH. Diagnosis was most frequently achieved by urinary or serum antigen positivity. People with PDH more frequently tested positive compared to those with OFH, but negative tests did not rule out histoplasmosis. Median time to diagnosis was prolonged among people with both PDH and OFH (32 vs. 31 days, respectively). Following diagnosis, people with PDH received more liposomal amphotericin (78.3% vs. 20%, P < .001). Subsequent survival at 90 and 365 days and treatment response were similar in both groups. Patients with PDH were more often hospitalized (95.7% vs. 60%, P = .006); however, once admitted, there were no differences in hospital length of stay or intensive care unit admission rate. The challenges of diagnosing histoplasmosis based on clinical presentation alone highlight the need for heightened awareness of these entities especially given the recent reports on expanded endemicity and delays in diagnosis.

Histoplasmosis is the most common endemic mycosis in North America. This article summarizes the clinical features, risk factors, and outcomes in patients who developed disseminated disease compared to more localized forms of histoplasmosis.

New Treatment Options for Refractory/Resistant CMV Infection.

Despite advances in monitoring and treatment, cytomegalovirus (CMV) infections remain one of the most common complications after solid organ transplantation (SOT). CMV infection may fail to respond to standard first- and second-line antiviral therapies with or without the presence of antiviral resistance to these therapies. This failure to respond after 14 days of appropriate treatment is referred to as "resistant/refractory CMV." Limited data on refractory CMV without antiviral resistance are available. Reported rates of resistant CMV are up to 18% in SOT recipients treated for CMV. Therapeutic options for treating these infections are limited due to the toxicity of the agent used or transplant-related complications. This is often the challenge with conventional agents such as ganciclovir, foscarnet and cidofovir. Recent introduction of new CMV agents including maribavir and letermovir as well as the use of adoptive T cell therapy may improve the outcome of these difficult-to-treat infections in SOT recipients. In this expert review, we focus on new treatment options for resistant/refractory CMV infection and disease in SOT recipients, with an emphasis on maribavir, letermovir, and adoptive T cell therapy.

Coronavirus Disease 2019-Associated Pulmonary Aspergillosis in Mechanically Ventilated Patients.

BACKGROUND: Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) occurs in critically ill patients with COVID-19. Risks and outcomes remain poorly understood. METHODS: A retrospective cohort study of mechanically ventilated adult patients with COVID-19 admitted to 5 Johns Hopkins hospitals was conducted between March and August 2020. CAPA was defined using composite clinical criteria. Fine and Gray competing risks regression was used to analyze clinical outcomes and, multilevel mixed-effects ordinal logistic regression was used to compare longitudinal disease severity scores. RESULTS: In the cohort of 396 people, 39 met criteria for CAPA. Patients with CAPA were more likely than those without CAPA to have underlying pulmonary vascular disease (41% vs 21.6%, respectively; P = .01), liver disease (35.9% vs 18.2%; P = .02), coagulopathy (51.3% vs 33.1%; P = .03), solid tumors (25.6% vs 10.9%; P = .02), multiple myeloma (5.1% vs 0.3%; P = .03), and corticosteroid exposure during the index admission (66.7% vs 42.6%; P = .005), and had lower body mass indexes (median, 26.6 vs 29.9 [calculated as weight in kilograms divided by height in meters squared]; P = .04). Patients with CAPA had worse outcomes, as measured by ordinal severity of disease scores, requiring longer time to improvement (adjusted odds ratio, 1.081.091.1; P < .001), and advancing in severity almost twice as quickly (subhazard ratio, 1.31.82.5; P < .001). They were intubated twice as long as those without CAPA (subhazard ratio, 0.40.50.6; P < .001) and had longer hospital stays (median [interquartile range], 41.1 [20.5-72.4) vs 18.5 [10.7-31.8] days; P < .001). CONCLUSION: CAPA is associated with poor outcomes. Attention to preventive measures (screening and/or prophylaxis) is warranted in people with high risk of CAPA.

Maribavir for Refractory Cytomegalovirus Infections With or Without Resistance Post-Transplant: Results From a Phase 3 Randomized Clinical Trial.

BACKGROUND: Therapies for refractory cytomegalovirus infections (with or without resistance [R/R]) in transplant recipients are limited by toxicities. Maribavir has multimodal anti-cytomegalovirus activity through the inhibition of UL97 protein kinase. METHODS: In this phase 3, open-label study, hematopoietic-cell and solid-organ transplant recipients with R/R cytomegalovirus were randomized 2:1 to maribavir 400 mg twice daily or investigator-assigned therapy (IAT; valganciclovir/ganciclovir, foscarnet, or cidofovir) for 8 weeks, with 12 weeks of follow-up. The primary endpoint was confirmed cytomegalovirus clearance at end of week 8. The key secondary endpoint was achievement of cytomegalovirus clearance and symptom control at end of week 8, maintained through week 16. RESULTS: 352 patients were randomized (235 maribavir; 117 IAT). Significantly more patients in the maribavir versus IAT group achieved the primary endpoint (55.7% vs 23.9%; adjusted difference [95% confidence interval (CI)]: 32.8% [22.80-42.74]; P < .001) and key secondary endpoint (18.7% vs 10.3%; adjusted difference [95% CI]: 9.5% [2.02-16.88]; P = .01). Rates of treatment-emergent adverse events (TEAEs) were similar between groups (maribavir, 97.4%; IAT, 91.4%). Maribavir was associated with less acute kidney injury versus foscarnet (8.5% vs 21.3%) and neutropenia versus valganciclovir/ganciclovir (9.4% vs 33.9%). Fewer patients discontinued treatment due to TEAEs with maribavir (13.2%) than IAT (31.9%). One patient per group had fatal treatment-related TEAEs. CONCLUSIONS: Maribavir was superior to IAT for cytomegalovirus viremia clearance and viremia clearance plus symptom control maintained post-therapy in transplant recipients with R/R cytomegalovirus. Maribavir had fewer treatment discontinuations due to TEAEs than IAT. Clinical Trials Registration. NCT02931539 (SOLSTICE).

Quantifying excess deaths among solid organ transplant recipients in the COVID-19 era.

Estimating the total coronavirus disease 2019 (COVID-19) mortality burden of solid organ transplant recipients (SOTRs), both directly through COVID-19 infection and indirectly through other impacts on the healthcare system and society, is critical for understanding the disease's impact on the SOTR population. Using SRTR data, we modeled expected mortality risk per month pre-COVID (January 2015-February 2020) for kidney/liver/heart/lung SOTRs, and compared monthly COVID-era deaths (March 2020-March 2021) to expected rates, overall and among subgroups. Deaths above expected rates were designated "excess deaths." Between March 2020 and March 2021, there were 3739/827/265/252 excess deaths among kidney/liver/heart/lung SOTRs, respectively, representing a 41.2%/27.4%/18.5%/15.0% increase above expected deaths. 93.0% of excess deaths occurred in patients age≥50. The observed:expected ratio was highest among Hispanic SOTRs (1.82) and lowest among White SOTRs (1.20); 56.0% of excess deaths occurred among Black or Hispanic SOTRs. 64.7% of excess deaths occurred among patients who had survived ≥5 years post-transplant. Excess deaths peaked in January 2021; geographic distribution of excess deaths broadly mirrored COVID-19 incidence. COVID-19 likely caused over 5000 excess deaths among SOTRs in the US in a 13-month period, representing 1 in 75 SOTRs and a substantial proportion of all deaths among SOTRs during this time. SOTRs will remain at elevated mortality risk until the COVID-19 pandemic can be controlled.

Heterologous Ad.26.COV2.S versus homologous BNT162b2/mRNA-1273 as a third dose in solid organ transplant recipients seronegative after two-dose mRNA vaccination.

Heterologous vaccination ("mixing platforms") for the third (D3) dose of SARS-CoV-2 vaccine is a potential strategy to improve antibody responses in solid organ transplant recipients (SOTRs), but data are mixed regarding potential differential immunogenicity. We assessed for differences in immunogenicity and tolerability of homologous (BNT162b2 or mRNA-1273; D3-mRNA) versus heterologous (Ad.26.COV2.S; D3-JJ) D3 among 377 SARS-CoV-2-infection naïve SOTRs who remained seronegative after two mRNA vaccines. We measured anti-spike titers and used weighted Poisson regression to evaluate seroconversion and development of high-titers, comparing D3-JJ to D3-mRNA, at 1-, 3-, and 6 month post-D3. 1-month post-D3, seroconversion (63% vs. 52%, p = .3) and development of high-titers (29% vs. 25%, p = .7) were comparable between D3-JJ and D3-mRNA recipients. 3 month post-D3, D3-JJ recipients were 1.4-fold more likely to seroconvert (80% vs. 57%, weighted incidence-rate-ratio: wIRR = 1.10 1.401.77 , p = .006) but not more likely to develop high-titers (27% vs. 22%, wIRR = 0.44 0.921.93 , p = .8). 6 month post-D3, D3-JJ recipients were 1.41-fold more likely to seroconvert (88% vs. 59%, wIRR = 1.04 1.411.93 , p = .029) and 2.63-fold more likely to develop high-titers (59% vs. 21%, wIRR = 1.38 2.635.00 , p = .003). There was no differential signal in alloimmune events or reactogenicity between platforms. SOTRs without antibody response after two mRNA vaccines may derive benefit from heterologous Ad.26.COV2.S D3.

Valganciclovir Dosing for Cytomegalovirus Prophylaxis in Solid-organ Transplant Recipients on Continuous Veno-venous Hemodialysis.

BACKGROUND: Optimal valganciclovir dosing for cytomegalovirus (CMV) prophylaxis in solid-organ transplant (SOT) patients on continuous veno-venous hemodialysis (CVVHD) is not known. Ganciclovir trough concentrations ≥0.60 µg/mL have been suggested for CMV prophylaxis. This study was conducted to determine if valganciclovir 450 mg enterally every 24 hours achieves ganciclovir trough concentrations ≥0.60 µg/mL in patients on CVVHD. METHODS: This single-center, prospective, open-label, pharmacokinetic study included adult SOT patients admitted to an intensive care unit from March 2018 to June 2019 on CVVHD. All patients were receiving valganciclovir 450 mg enterally every 24 hours for CMV prophylaxis prior to enrollment. Each patient had a peak and trough sample drawn at steady state. RESULTS: Ten SOT patients were included in the study (6 liver, 1 simultaneous liver-kidney, 2 bilateral lung, 1 heart). The mean ± SD age was 51.8 ± 14.0 years, and average body mass index was 27 ± 6.9 kg/m2. Ganciclovir trough concentrations ranged from 0.31 to 3.16 µg/mL, and 80% of participants have trough concentrations ≥0.60 µg/mL. No patients had documented neutropenia while on valganciclovir and CVVHD; 60% of patients had significant thrombocytopenia. CONCLUSIONS: Valganciclovir 450 mg enterally every 24 hours achieved ganciclovir trough concentrations ≥0.60 µg/mL in most patients on CVVHD, similar to those reported with intravenous ganciclovir for prophylaxis in this population. Based on these data, valganciclovir may require dosing every 24 hours to achieve concentrations equivalent to ganciclovir. Neutropenia did not occur in the study period. Thrombocytopenia was common and likely multifactorial.

Liver transplantation in the United States during the COVID-19 pandemic: National and center-level responses.

COVID-19 has profoundly affected the American health care system; its effect on the liver transplant (LT) waitlist based on COVID-19 incidence has not been characterized. Using SRTR data, we compared observed LT waitlist registrations, waitlist mortality, deceased donor LTs (DDLT), and living donor LTs (LDLT) 3/15/2020-8/31/2020 to expected values based on historical trends 1/2016-1/2020, stratified by statewide COVID-19 incidence. Overall, from 3/15 to 4/30, new listings were 11% fewer than expected (IRR = 0.84 0.890.93 ), LDLTs were 49% fewer (IRR = 0.37 0.510.72 ), and DDLTs were 9% fewer (IRR = 0.85 0.910.97 ). In May, new listings were 21% fewer (IRR = 0.74 0.790.84 ), LDLTs were 42% fewer (IRR = 0.39 0.580.85 ) and DDLTs were 13% more (IRR = 1.07 1.151.23 ). Centers in states with the highest incidence 3/15-4/30 had 59% more waitlist deaths (IRR = 1.09 1.592.32 ) and 34% fewer DDLTs (IRR = 0.50 0.660.86 ). By August, waitlist outcomes were occurring at expected rates, except for DDLT (13% more across all incidences). While the early COVID-affected states endured major transplant practice changes, later in the pandemic the newly COVID-affected areas were not impacted to the same extent. These results speak to the adaptability of the transplant community in addressing the pandemic and applying new knowledge to patient care.

Inpatient COVID-19 outcomes in solid organ transplant recipients compared to non-solid organ transplant patients: A retrospective cohort.

Immunosuppression and comorbidities might place solid organ transplant (SOT) recipients at higher risk from COVID-19, as suggested by recent case series. We compared 45 SOT vs. 2427 non-SOT patients who were admitted with COVID-19 to our health-care system (March 1, 2020 - August 21, 2020), evaluating hospital length-of-stay and inpatient mortality using competing-risks regression. We compared trajectories of WHO COVID-19 severity scale using mixed-effects ordinal logistic regression, adjusting for severity score at admission. SOT and non-SOT patients had comparable age, sex, and race, but SOT recipients were more likely to have diabetes (60% vs. 34%, p < .001), hypertension (69% vs. 44%, p = .001), HIV (7% vs. 1.4%, p = .024), and peripheral vascular disorders (19% vs. 8%, p = .018). There were no statistically significant differences between SOT and non-SOT in maximum illness severity score (p = .13), length-of-stay (sHR: 0.9 1.11.4 , p = .5), or mortality (sHR: 0.1 0.41.6 , p = .19), although the severity score on admission was slightly lower for SOT (median [IQR] 3 [3, 4]) than for non-SOT (median [IQR] 4 [3-4]) (p = .042) Despite a higher risk profile, SOT recipients had a faster decline in disease severity over time (OR = 0.76 0.810.86 , p < .001) compared with non-SOT patients. These findings have implications for transplant decision-making during the COVID-19 pandemic, and insights about the impact of SARS-CoV-2 on immunosuppressed patients.

Quantifying infection risks in incompatible living donor kidney transplant recipients.

Desensitization has enabled incompatible living donor kidney transplantation (ILDKT) across HLA/ABO barriers, but added immunomodulation might put patients at increased risk of infections. We studied 475 recipients from our center from 2010 to 2015, categorized by desensitization intensity: none/compatible (n = 260), low (0-4 plasmaphereses, n = 47), moderate (5-9, n = 74), and high (≥10, n = 94). The 1-year cumulative incidence of infection was 50.1%, 49.8%, 66.0%, and 73.5% for recipients who received none, low, moderate, and high-intensity desensitization (P < .001). The most common infections were UTI (33.5% of ILDKT vs. 21.5% compatible), opportunistic (21.9% vs. 10.8%), and bloodstream (19.1% vs. 5.4%) (P < .001). In weighted models, a trend toward increased risk was seen in low (wIRR = 0.77 1.402.56 ,P = .3) and moderately (wIRR = 0.88 1.352.06 ,P = .2) desensitized recipients, with a statistically significant 2.22-fold (wIRR = 1.33 2.223.72 ,P = .002) increased risk in highly desensitized recipients. Recipients with ≥4 infections were at higher risk of prolonged hospitalization (wIRR = 2.62 3.574.88 , P < .001) and death-censored graft loss (wHR = 1.15 4.0113.95 ,P = .03). Post-KT infections are more common in desensitized ILDKT recipients. A subset of highly desensitized patients is at ultra-high risk for infections. Strategies should be designed to protect patients from the morbidity of recurrent infections, and to extend the survival benefit of ILDKT across the spectrum of recipients.

Update on cytomegalovirus in transplant recipients: new agents, prophylaxis, and cell-mediated immunity.

PURPOSE OF REVIEW: This review is an overview of recent advances in diagnostics, therapies, and prevention strategies for cytomegalovirus (CMV), focusing on solid-organ transplant and hematopoietic stem cell transplant recipients. RECENT FINDINGS: A randomized trial of prophylaxis vs preemptive therapy in donor-seropositive, recipient-seronegative liver transplant recipients found significantly less CMV disease in the preemptive group. Maribavir has shown promise for the treatment of resistant/refractory CMV and for uncomplicated CMV DNAemia. A post hoc mortality analysis, as well as emerging reports of real-world and off-label use, have expanded the spectrum of clinical experience with letermovir. The first interventional trials using CMV cell-mediated immune assays have been published and showed promising results for delineating antiviral strategies. New data from additional interventional trials are expected soon. SUMMARY: The past 1-2 years have seen major developments in the area of CMV management in transplant recipients. Expanding diagnostic and therapeutic capabilities provide a foundation for optimizing strategies in the future, to reduce morbidity and mortality from CMV.

Safety and efficacy of intravenously administered cidofovir in adult haematopoietic cell transplant recipients: a retrospective multicentre cohort study.

OBJECTIVES: To evaluate the safety and efficacy of cidofovir for the treatment of double-stranded DNA (dsDNA) viral infections following allogeneic haematopoietic cell transplant (HCT). METHODS: This was a retrospective multicentre cohort study including adult HCT recipients who received ≥1 dose of IV-administered cidofovir for any dsDNA viral infection from 2006 to 2019. The objectives were to describe the rate of and risk factors for nephrotoxicity and virological response by the end of treatment (EOT). RESULTS: We included 165 patients from nine centres. Cidofovir was administered at 5 mg/kg/week (N = 115; 69.7%), 1 mg/kg/week (18; 10.9%), 3 mg/kg/week (12; 7.3%) or 1 mg/kg three times/week (11; 6.7%). Cidofovir was administered for adenovirus, cytomegalovirus (CMV) and BK virus infection in 75 (45.5%), 64 (38.8%) and 51 (30.9%) patients, respectively. Among 158 patients with renal function data at baseline and EOT, 40 (25.3%) developed nephrotoxicity. In multivariable analyses, age (OR 1.04; P = 0.05), weight (OR 1.05; P = 0.01), CMV infection (OR 3.6; P = 0.02), liposomal amphotericin B (OR 8.06; P = 0.05) and IV voriconazole/posaconazole (OR 13.0; P = 0.003) were predictors of nephrotoxicity. Creatinine concentration was significantly higher at EOT (1.16 ±â€Š0.95 mg/dL) compared with baseline (0.91 ±â€Š0.39 mg/dL; P < 0.001), but improved by 2 weeks (0.91 ±â€Š0.84 mg/dL; P = 0.007) and 4 weeks (0.96 ±â€Š0.89 mg/dL; P = 0.03) post-EOT. Median viral load significantly declined for patients with adenovirus DNAaemia by EOT (P < 0.0001) and for patients with CMV DNAaemia by EOT + 4 weeks (P = 0.003), but not for patients with BK virus DNAaemia. CONCLUSIONS: One in four HCT recipients treated with IV cidofovir developed largely reversible nephrotoxicity. Careful selection of patients and close follow-up of renal function may minimize toxicity.

Interleukin-18 and tumor necrosis factor-α are elevated in solid organ transplant recipients with possible cytomegalovirus end-organ disease.

End-organ cytomegalovirus (CMV) disease can be life threatening to solid organ transplant recipients. Diagnosis is often complicated by variation in amount of CMV DNA in plasma and the need for an invasive procedure to obtain a biopsy of the suspected affected organ, which can delay recognition and treatment. Several inflammatory cytokines are elevated in CMV disease, and the purpose of this study was to determine if they could be used to distinguish solid organ transplant recipients with CMV DNAemia alone from those with possible end-organ CMV disease. We found that regardless of pre-transplant CMV serostatus, plasma interleukin (IL)-18, tumor necrosis factor-α (TNF-α), and amount of CMV DNA in plasma were increased in possible end-organ CMV disease, with elevated IL-18 associated with increased odds of possible end-organ CMV disease even after adjusting for amount of CMV DNA. These findings highlight IL-18 and TNF-α as potential non-invasive markers of possible end-organ CMV disease regardless of transplanted organ or serostatus in solid organ transplant recipients.

Outcomes of transplant recipients treated with cidofovir for resistant or refractory cytomegalovirus infection.

BACKGROUND: Treatment of ganciclovir-resistant (GCV-R)/refractory cytomegalovirus (CMV) infections in blood/marrow transplant (BMT) and solid organ transplant (SOT) recipients remains suboptimal. Cidofovir (CDV), a nucleotide analogue with anti-CMV activity, is nephrotoxic and oculotoxic. METHODS: We retrospectively evaluated the outcomes of SOT and BMT patients with GCV-R/refractory CMV treated with CDV between 1/1/2008 and 12/31/2017. DATA COLLECTED: baseline demographics, CMV serostatus, clinical and virologic presentations and outcomes, UL97 and UL54 genotype mutations, drug toxicities, and cause of death. Descriptive statistics were used. RESULTS: 16 patients received CDV for treatment of CMV: six BMT and 10 SOT. Seven (47%) of the patients had high-risk donor/recipient serostatus: six (60%) SOT were D+/R-; one (16.7%) BMT was D-/R+. Median time to CMV DNAemia was 131 days post-transplant (IQR, 37.5-230.3). Proven tissue invasive disease was present in three patients (18.8%). Twelve (75%) had genotype testing; 10 (83.3%) of those had antiviral resistance mutations. While on CDV, six (37.5%) developed nephrotoxicity, and four (25%) developed uveitis (two had both uveitis and nephrotoxicity). Eight (50%) had failure to clear CMV DNAemia despite CDV treatment. Eight (50%) of the patients died; median time to death, after initiation of CDV, was 33.5 days [IQR22-988]. CONCLUSIONS: In the absence of good therapeutic alternatives, CDV is used in GCV-R/refractory CMV infection. However, it is associated with a substantial risk of toxicity and failure to clear CMV DNAemia, highlighting the need for development of newer and less toxic therapies. The high mortality in this group of patients underscores the severity of illness in this population.