For Review 1 1 Incidence, features and outcomes of Cytomegalovirus DNAemia in unmanipulated 2 haploidentical allogeneic hematopoietic stem cell transplantation with post- 3 transplantation cyclophosphamide 4 5 Dixie Huntley1, Estela Giménez1, María Jesús Pascual2, Juan Carlos Hernández-Boluda3, 6 Beatriz Gago2, Lourdes Vázquez4, José Luis Piñana3, Magdalena García4, Ariadna Pérez3, 7 David Serrano5, Marta Hernández5, Eliseo Albert1, Carlos Solano3,6, and David Navarro1,7 8 9 1Microbiology Service, Hospital Clínico Universitario, INCLIVA ResearchInstitute, 10 Valencia, Spain 11 2Hematology Service, Hospital Regional Universitario, Málaga, Spain. 12 3Hematology Service, Hospital Clínico Universitario, INCLIVA ResearchInstitute, 13 Valencia, Spain. 14 4Hematology Service, Hospital Clínico Universitario, Salamanca, Spain. 15 5Hematology Service, Hospital General Universitario Gregorio Marañón, Madrid, Spain. 16 6Department of Medicine, School of Medicine, University of Valencia, Valencia, Spain. 17 7Department of Microbiology, School of Medicine, University of Valencia, Valencia, 18 Spain. 19 Running Title: CMV DNAemia in haploidentical allo-HSCT. 20 Acknowledgements Page 2 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 2 21 Estela Giménez holds a Juan Rodés research contract from the Carlos III Health Institute 22 (Ref.JR18/00053). Eliseo Albert holds a Río Hortega research contract from the Carlos 23 III Health Institute (Ref.CM18/00221). 24 This research was supported by grant 15/0090 from FIS (Fondo de 25 InvestigacionesSanitarias), Ministerio de Sanidad y Consumo, Spain. 26 The authors report no conflicts of interest 27 28 Correspondence: David Navarro, Microbiology Service, Hospital ClínicoUniversitario, 29 and Department of Microbiology, School of Medicine, Av. Blasco Ibáñez 17, 46010 30 Valencia, Spain. Phone: +34 963864657; Fax: +3963864173; E-mail: 31 david.navarro@uv.es. 32 33 34 35 36 37 38 39 40 41 Page 3 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 3 42 Abstract 43 Background: Conflicting data have been published as to the risk of cytomegalovirus 44 (CMV) DNAemia and CMV disease in patients undergoing haploidentical hematopoietic 45 stem cell transplantation (Haplo-HSCT) with post-transplantation cyclophosphamide. 46 Methods: We conducted a multicenter retrospective study including 118 patients 47 subjected to unmanipulated Haplo-HSCT to further clarify this issue. An historic cohort 48 comprising 165 patients undergoing other transplant modalities (HLA-matched related, 49 matched unrelated or mismatched) was built for comparison purposes. Plasma CMV 50 DNA monitoring was performed using two highly sensitive real-time PCR assays. 51 Results: Overall, the cumulative incidence of CMV DNAemia, recurrent CMV 52 DNAemia and CMV DNAemia requiring preemptive antiviral therapy in patients 53 undergoing Haplo-HSCT was 63.9%, 34.9% and 50.1%, respectively. These figures were 54 rather comparable for other transplant modalities (P=0.22, P=0.13 and P=0.72, 55 respectively). A trend towards longer duration of episodes and shorter CMV DNA 56 doubling times was observed in Haplo-HSCT patients in comparison with other transplant 57 modalities. Furthermore, median CMV DNA peak load was significantly higher in Haplo- 58 HSCTs (P=0.008), yet overall mortality by day 180 and 365 was the same across 59 comparison groups. There were five cases of CMV disease and all occurred in Haplo- 60 HSCT patients. This latter observation is worrying and merits further investigation. 61 Conclusions: The incidence of initial and recurrent episodes of CMV DNAemia either 62 requiring or not antiviral therapy in unmanipulated Haplo-HSCT was comparable to other 63 transplant modalities in our cohort. 64 . Page 4 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 4 65 66 Key words: Cytomegalovirus (CMV), CMV DNAemia, haploidenticalhematopoietic 67 stem cell transplantation, overall mortality. 68 69 70 Introduction 71 Haploidentical hematopoietic stem cell transplantation (Haplo-HSCT) with 72 posttransplantation cyclophosphamide (PT-Cy) is being increasingly used as the first- 73 choice platform for treatment of high-risk hematological malignancies, in the absence of 74 a suitable HLA-matched donor. The potential advantages of Haplo-HSCT lie in the wide 75 and rapid availability of donors and comparable clinical outcomes to other alternative 76 allogeneic stem cell transplant (allo-HSCT) modalities1-5. 77 Cytomegalovirus (CMV) remains a threat for allo-HSCT recipients despite the 78 availability of effective strategies for the prevention of end-organ disease (i.e. preemptive 79 therapy)6, since viral DNAemia itself may be detrimental in terms of survival7-11. 80 Conflicting data have been published as to the incidence of CMV DNAemia and CMV 81 disease in haplo-HSCT recipients, with some studies suggesting that this transplant 82 modality harbors a significantly higher risk for both events when compared to HLA- 83 matched related or unrelated allo-HSCTs12-22; yet this appeared not to have an impact on 84 overall (OM) and non-relapse (NRM) mortality18,23-25. In the current multicenter study we 85 estimated the incidence of CMV DNAemia, CMV disease OM and NRM in Haplo-allo- 86 HSCT and compared to that in other transplant modalities. Additionally, we provide Page 5 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 5 87 comparative data regarding the dynamics of CMV DNAemia across donor types, which 88 to our knowledge have not been thoroughly investigated. 89 Patients and methods 90 Study population 91 In this multicenter, observational study, we retrospectively reviewed CMV DNA PCR 92 results and clinical charts of 283 patients who underwent allo-HSCT in four Spanish 93 institutions. 94 A total of 118 consecutive patients who underwent Haplo-HSCT with cyclophosphamide 95 (50mg/kg/day on days 3 and 5 after transplantation) at the Hospital Clínico Universitario 96 of Valencia-HCUV- (n=63), Hospital Regional Universitario of Málaga, Spain –HRUM- 97 (n=16), Hospital Clínico Universitario of Salamanca, Spain-HCUS- (n=30), or Hospital 98 General Universitario Gregorio Marañón of Madrid, Spain –HGUGM- (n=9), between 99 January 2016 and December 2018 were included in the current study. In turn, a historical 100 cohort was built that included a total of 165 consecutive patients undergoing other allo- 101 HSCT modalities at two of these centers (HCUV, n=137 from May 2012 to June 2018, 102 and HRUM, n=28 from January 2016 to February 2018). Of these, 76 were HLA- 103 matched-related (MRD), 62 HLA-matched unrelated (MUD) and 27 HLA-mismatched 104 either related-MMRD (n=24) or unrelated –MMUD- (n=3) (n=27). All but 8 patients were 105 followed up through day 365. These 8 patients were followed up for a median of median 106 294 days (227-328). This study was approved by the Hospital Clínico, Fundación 107 INCLIVA Ethics Committee. Signed informed consent was obtained from participants. 108 Management of CMV infection Page 6 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 6 109 CMV infection was managed in all patients by a preemptive antiviral therapy approach. 110 Plasma CMV DNA load was monitored using the CMV RealTime CMV PCR (Abbott 111 Molecular, Des Plaines, IL, USA), whose limit of detection (LOD) is approximately 31 112 IU/ml (95% C.I.)26, at all centers except at HCUS in which the Affigene CMV Trender 113 kit (Cepheid AB, Bromma, Sweden) was used27; the LOD of this assay is 137 IU/ml, 114 according to the manufacturer. CMV DNA load monitoring was conducted on a weekly 115 basis through day +100. From day +100 until day +365 patients at risk for recurrent 116 episodes of CMV DNAemia were also monitored on a weekly basis, while the remaining 117 patients were monitored at each planned visit. Preemptive antiviral therapy with oral 118 valganciclovir (900 mg/12 h), iv. ganciclovir (5 mg/kg/12 h), or foscarnet (60mg/kg/12 119 h) was initiated at HCUV when the plasma CMV DNA load reached levels of ≥1,500 120 IU/ml, or when the CMV doubling time (dt) was ≤2.0 days, whichever occurred first (this 121 latter strategy since May 2014)28. CMV DNA threshold for inception of preemptive 122 therapy was ≥600 IU/ml at HCUS, ≥156 IU/ml at HRUM and any level at HGUGM. 123 CMV disease was diagnosed and treated as previously detailed6. 124 CMV DNA kinetics parameters 125 The CMV DNA doubling time was given by dt = (t2 − t1) × [ln2/ln(q2/q1)], with q1 and 126 t1 representing the CMV DNA (copies/ml) at the time of the first positive qRT-PCR (in 127 days), respectively, and q2 and t2 representing CMV DNA at the time of the second 128 positive qRT-PCR (in the absence of antiviral treatment)29. Only episodes showing an 129 increase between the first and second CMV DNA load values of >3-fold were considered 130 for analysis. The kinetics of CMV DNA load clearance is expressed by the equation yt= 131 y0e-kt, where y0 is the peak CMVDNA load, t is time elapsed between y0 and ytand k is 132 the decay constant29. Page 7 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 7 133 Definitions 134 CMV DNAemia was defined as detection of CMV DNA at any level in one or more 135 plasma specimens. The overall duration of a given episode of viral DNAemia was the 136 time elapsed between the day of first detection of viral DNA in plasma and that of the 137 first negative (undetectable) PCR result. Recurrent episodes were those that developed at 138 least 15 days after clearance of the previous one. Acute graft versus host disease (aGvHD) 139 was diagnosed and graded as previously reported30. 140 Statistical analysis 141 The cumulative incidence of events of interest was estimated by the cumulative incidence 142 method using the statistical software R (http://www.r-project.org/) with the survival and 143 cmprsk packages. The Fine-Gray test was used for comparisons. Overall mortality (OM) 144 was defined as the total number of deaths from any cause. Non-relapse mortality (NRM) 145 was defined as the total number of deaths without relapse or recurrence; the occurrence 146 of relapse or progression was considered a competitive event and censored. The 147 cumulative incidence of CMV DNAemia was calculated considering death and relapse as 148 competitive events. Cox proportional hazards regression models were used to assess the 149 potential risk factors for OM and NRM, as previously reported10. Post-transplant events 150 such as CMV DNAemia and acute Graft versus Host Disease (aGvHD) were treated as 151 time-dependent variables. For multivariate analyses, only variables with parameter 152 estimates showing a P value ≤ 0.10 in the univariate analyses were included; two-sided 153 P-values= <0.05 were deemed to be significant. Differences between medians were 154 compared using the Mann-Whitney U-test and the Kruskal-Wallis test, when appropriate. 155 The latter statistical analyses were performed using SPSS version 20.0 (SPSS, Chicago, 156 IL, USA). Page 8 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 http://www.r-project.org/ For Review 8 157 Results 158 Clinical characteristics of patients 159 Demographics, baseline and post-transplant characteristics of patients undergoing 160 different transplant modalities are shown in Table 1. Sex, age, underlying diseases, 161 conditioning regimen used and incidence of aGvHD were comparable across groups, 162 which in turn differed in parameters linked to the allo-HSCT platform selected (i.e. use 163 of ATG), or aGvHD prophylaxis regimens (i.e. use of PT-Cy). Of note, the 164 donor/recipient CMV serostatus pair D-/R+ was underrepresented in patients undergoing 165 haploidentical and MRD transplantation 166 Incidence of CMV DNAemia in unmanipulated Haplo-HSCT and in other transplant 167 modalities 168 Overall, the cumulative incidence of CMV DNAemia in patients undergoing Haplo- 169 HSCT was 63.9% (95% CI, 55%-72.6%). This figure was lower at HCUS (48.4%- 95% 170 CI, 30%-67%) than at the other participating centers: HCUV (71%; 95% CI, 60%-83%, 171 HRUM 56% (95% CI, 29%-84%), and HGUGM78% (95% CI, 44%-100%). In this sense 172 it is noteworthy that the LOD of the Affigene PCR assay, used at HCUS, is higher (less 173 sensitive) than that of the Abbott PCR assay (used at the remaining centers). For patients 174 subjected to MRD, MUD and MMUR or MMRD allo-HSCTs (all monitored with the 175 Abbott PCR assay) the cumulative incidence of CMV DNAemia was 73.7% (95% CI, 176 63.6%-83.8%), 80.7% (95% CI, 70.5%-90.8%) and 70.4% (95% CI, 52%-88.8%), 177 respectively. Figure 1 shows the data for patients monitored with the Abbott PCR assay 178 (n=252): the cumulative incidence of CMV DNAemia appeared to be comparable across 179 the different transplant modalities (P=0.22). In our series, no risk factors for the Page 9 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 9 180 occurrence of CMV DNAemia in Haplo-HSCT were identified other than recipient CMV 181 seropositivity. This was so both when the entire cohort was considered for the analyses 182 (Table 2) and when only patients monitored with the Abbott PCR assay were included 183 (data not shown) 184 Overall, the cumulative incidence of recurrent CMV DNAemia in Haplo-HSCT was 34% 185 (95% CI, 23%-45%); this figure was not significantly different (P=0.13) from that seen 186 in patients who underwent MRD (44.6%; 95% CI, 31%-58%), MUD (44%; 95% CI, 30%- 187 58%) and MMRD or MMUD (63%; 95% CI, 39%-87%). Nevertheless, the cumulative 188 incidence of recurrent episodes receiving PET was higher in MMRD and MMUD than 189 in haploidentical, MUD and MRD modalities (Figure 2). 190 We next assessed the incidence of episodes of CMV DNAemia that required 191 administration of preemptive antiviral therapy (CMV PET). Overall cumulative incidence 192 of CMV PET (including initial and recurrent episodes) was not differerent across the 193 donor types (P=0.72): 50.9% (95% CI, 31.7%-72%) in Haplo-HSCT, 44.7% (95% CI, 194 33%-56%) in MRD, 43.6% (95% CI, 30.8%-56%) in MUD and 51.9% (95% CI, 31.7%- 195 72%) in MMRD or MMUD. This was also the case (P=0.22) when only first episodes of 196 CMV DNAemia were analyzed: 50% (95% CI, 41%-59%) in Haplo-HSCT, 36.8% (95% 197 CI, 26%-48%) in MRD, 37% (95% CI, 25%-49% in MUD and 40.7% (95% CI, 21%- 198 61%) in MMRD/MMUD. 199 To control for the potential impact of the CMV DNA threshold triggering PET in the 200 results, we performed a subanalysis including only patients attended at the HCUV 201 (consistent criterion for PET inception throughout the study period), which comprised the 202 majority of patients in our series. As shown in Figure 3, no significant differences were Page 10 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 10 203 found, regardless of whether all episodes documented throughout the study follow-up (3A) 204 or only initial episodes (3B) were considered for the analyses. 205 Incidence of CMV disease 206 Five of the 118 patients undergoing Haplo-HSCT developed CMV disease (cumulative 207 incidence, 4.5%; 95% CI, 0.5-7.9%), in all cases involving the gastro-intestinal tract. Two 208 cases were documented at HCUV, two at HCUS and one at HRUM. Relevant virological 209 characteristics of these clinical episodes are displayed in Table 4. Of note: in one patient 210 CMV DNAemia was not documented, preemptive antiviral therapy was started in 3 out 211 of the 5 patients and the CMV DNA dt could only be calculated (according to established 212 criteria) in one patient. No cases of CMV disease were diagnosed in control patients 213 undergoing other allo-HSCT modalities (at HCUV and HRUM) (P=0.74). 214 Kinetics of CMV DNAemia in Haplo-HSCT and other transplant modalities 215 We next investigated the kinetics of initial episodes of CMV DNAemia in patients 216 undergoing different allo-HSCT donor types. For these analyses, as detailed in the 217 footnotes of Table 3, we selected specific subgroups of patients (episodes) to ensure 218 homogeneity. No differences were seen across transplant modalities regarding the 219 timeframe of CMV DNAemia documentation, the magnitude of initial CMV DNA load 220 or the CMV DNA half-life, in either treated or untreated episodes (Table 3). A trend 221 towards longer duration of episodes and shorter CMV DNA dts was observed in Haplo- 222 HSCT patients in comparison with other transplant platforms. Furthermore, median CMV 223 DNA peak load was significantly higher in Haplo-HSCTs (P=0.007). 224 CMV DNAemia, all-cause and non-relapse mortality Page 11 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 11 225 A total of 58 and 74 patients had died by day 180 (Haplo-HSCT, n=24; MRD, n=13; 226 MUD, n=13 and MMUD, n=8) and 365 (Haplo-HSCT, n=33; MRD, n=18; MUD, n=15, 227 and MMUD, n=8) after allo-HSCT. The causes of death are shown in Supplementary 228 Table 1. As shown in Figure 4, neither OM nor NRM was different across comparison 229 groups. 230 Discussion 231 In this retrospective multicenter study including a relatively large cohort of patients 232 undergoing T-cell replete Haplo-HSCT we found an overall cumulative incidence of 233 CMV DNAemia of 63.9% by day 365 after transplantation, slightly higher than reported 234 in other fairly comparable series (ranging from 30% to 55%)12-14,18-20. Several non- 235 mutually exclusive factors may account for this apparent discrepancy, including different 236 follow-up lengths, the choice of immunosuppressive regimens for aGvHD prevention (i.e. 237 either including or not sirolimus31), the blood specimen for CMV DNA surveillance 238 (whole blood vs. plasma) or the use of real-time PCRs for CMV DNA detection 239 displaying distinct limits of detection. Regarding the latter issue, the cumulative incidence 240 of CMV DNAemia was lower at HCUS (48.4%), where the Affigene Trender CMV PCR 241 kit was used, than at the other participating centers (ranging from 56% to 78%), in which 242 a more sensitive PCR assay (Abbott) was employed. Notwithstanding, these figures are 243 substantially lower than those reported for Haplo-HSCT with combined used of 244 cyclophosphamide and ATG, which could be as high as 87% 15,20. 245 In our Haplo-HSCT cohort only recipient CMV seropositivity was associated with an 246 increased risk of CMV DNAemia. Use of high-dose corticosteroids for severe aGvHD14, 247 or conditioning regimens containing myeloablative doses of busulfan19, or preceding Page 12 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 12 248 HHV-6 DNAemia32 have been reported to be associated with higher rates of CMV 249 DNAemia in patients undergoing unmanipulated Haplo-HSCT. 250 In our experience, the cumulative incidence of CMV DNAemia in Haplo-HSCT patients 251 was not different from that in patients undergoing other all-HSCT modalities, including 252 MRD, MUD or MMRD/MMUD, in line with previous observations14,18. A novel finding 253 of the current study was that the rate of recurrent CMV DNAemia as well as the 254 percentage of episodes that required PET administration, irrespective of whether they 255 were initial or recurrent, were rather comparable across the different transplant platforms. 256 Occurrence of CMV disease in patients undergoing Haplo-HSCT with or without T-cell 257 depletion has been consistently reported as high, ranging from 11% to 17%12-15, compared 258 to those in other allo-HSCT modalities (less than 10%)6. In a recent survey across 259 Spanish centers performing all types of allo-HSCTs in adult patients the cumulative 260 incidence of CMV disease was 2.8%33. In our study, although CMV disease was 261 documented in 4.5% of patients, all cases (n=5) developed in the context of Haplo-HSCT. 262 The current study makes a novel contribution to the literature in providing insight into the 263 kinetics of CMV DNAemia in unmanipulated Haplo-HSCT. We observed a trend towards 264 longer duration of initial episodes of CMV DNAemia and shorter CMV DNA dts and 265 significantly higher median CMV DNA peak loads in Haplo-HSCT patients than in those 266 undergoing other transplant modalities. This occurred despite the fact that the 267 donor/recipient CMV serostatus pair D-/R+, convincingly associated with a protracted 268 reconstitution of CMV-specific T-cell immunity6, was underrepresented in patients 269 undergoing Haplo-HSCT compared to other allo-HSCT platforms (MUD and 270 MMRD/MMUD). Page 13 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 13 271 The above observation could be explained, at least in part, by the delay in CD4+ T-cell 272 reconstitution apparently experienced by patients undergoing Haplo-HSCT, in 273 comparison with HLA-matched allo-HSCTs34. This might also account for the increased 274 incidence of CMV disease seemingly occurring in our cohort and reported by other 275 groups12-15 and the high rate of CMV drug resistance among patients receiving PET after 276 Haplo-HSCT, presumably linked to persistent viral replication14. In the absence of data 277 on CMV-specific T-cell immunity, this is nevertheless merely speculative, yet our data 278 suggest that OM and NRM in patients undergoing Haplo-HSCT by days 180 and 365 are 279 not different from that in patients subjected to other allo-HSCT types, as has been 280 previously reported18,23-25. 281 There are several limitations in our study. The first and main one is the relatively high 282 heterogeneity across the study and historical cohorts. In particular, no patients undergoing 283 non-Haplo-HSCT from two centers HGUS and HGUGM were included. Nevertheless, 284 this is in our view unlikely to have had any impact on the conclusions reached, as allo- 285 HSCT management at these centers within the study period was largely comparable to 286 that in the other two centers (HCUV and HRUM) (not shown). Second, different CMV 287 PET strategies were used across centers; despite this, subanalyses performed with patients 288 attended at HCUV led to similar conclusions to those reached when all patients in this 289 series were taken into consideration. Third, no data on CMV-specific T-cell immunity 290 were provided, and finally, the robustness of mortality analyses was hampered by the 291 sample size. 292 In summary, our study suggests that unmanipulated Haplo-HSCT increases neither the 293 risk of CMV DNAemia and recurrent CMV DNAemia, as documented by highly- 294 sensitive real-time PCR assays, nor the need for preemptive antiviral therapy and OM and Page 14 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 14 295 NRM. Nevertheless, the data presented herein relative to certain kinetics parameters of 296 CMV DNAemia (i.e. duration of the episodes and CMV DNA dt and peak levels) and the 297 seemingly high incidence of CMV disease in these patients should be taken seriously into 298 consideration and further studies to clarify this are warranted. 299 References 300 1. 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Page 17 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 17 359 16. Chen Y, Xu LP, Liu KY, Chen H, Chen YH, Zhang XH et al. Risk factors for 360 cytomegalovirus DNAemia following haploidentical stem cell transplantation 361 and its association with host hepatitis B virus serostatus. J ClinVirol 362 2016;75:10-15. 363 17. Hammerstrom AE, Lombardi LR, Pingali SR, Rondon G, Chen J, Milton DR et 364 al. Prevention of Cytomegalovirus Reactivation in Haploidentical Stem Cell 365 Transplantation. Biol Blood Marrow Transplant 2018; 24:353-358. 366 18. Baker M, Wang H, Rowley SD, Cai L, Pecora AL, Skarbnik A et al. 367 Comparative outcomes after haploidentical or unrelated donor bone marrow or 368 blood stem cell transplantation in adult patients with hematological 369 malignancies. Biol Blood Marrow Transplant 2016; 22: 2047–2055. 370 19. Raj RV, Hari P, Pasquini M, Epperla N, D'Souza A, Fenske T et al. Impact of 371 haploidentical hematopoietic cell transplantation conditioning intensity on the 372 incidence and severity of post-transplantation viral infections. Bone Marrow 373 Transplant 2016;51:1602-1604. 374 20. Tischer J, Engel N, Fritsch S, Prevalsek D, Hubmann M, Schulz C et al. Virus 375 infection in HLA-haploidentical hematopoietic stem cell transplantation: 376 incidence in the context of immune recovery in two different transplantation 377 settings. Ann Hematol 2015;94:1677-88. 378 21. Chang YJ, Zhao XY, Huo MR, Xu LP, Liu DH, Liu KY et al. Immune 379 reconstitution following unmanipulated HLA-mismatched/haploidentical Page 18 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 18 380 transplantation compared with HLA-identical sibling transplantation. J Clin 381 Immunol2012;32:268-280. 382 22. Crocchiolo R, Bramanti S, Vai A, Sarina B, Mineri R, Casari E et al. Infections 383 after T-replete haploidentical transplantation and high-dose cyclophosphamide 384 as graft-versus-host disease prophylaxis. Transpl Infect Dis 2015;17:242-249. 385 23. Cesaro S, Crocchiolo R, Tridello G, Knelange N, Van Lint MT, Koc Y et al. 386 Comparable survival using a CMV-matched or a mismatched donor for CMV+ 387 patients undergoing T-replete haplo-HSCT with PT-Cy for acute leukemia: a 388 study of behalf of the infectious diseases and acute leukemia working parties of 389 the EBMT. Bone Marrow Transplant 2018;53:422-430. 390 24. Slade M, DiPersio JF, Westervelt P, Vij R, Schroeder MA, Romee R. 391 Haploidentical Hematopoietic Cell Transplant with Post-Transplant 392 Cyclophosphamide and Peripheral Blood Stem Cell Grafts in Older Adults with 393 Acute Myeloid Leukemia or Myelodysplastic Syndrome. Biol Blood Marrow 394 Transplant 2017;23:1736-1743. 395 25. Di Stasi A, Milton DR, Poon LM, Hamdi A, Rondon G, Chen J et al. Similar 396 transplantation outcomes for acute myeloid leukemia and myelodysplastic 397 syndrome patients with haploidentical versus 10/10 human leukocyte antigen- 398 matched unrelated and related donors. BiolBloodMarrowTransplant 2014 399 ;20:1975-1981. 400 26. Clari MÁ, Bravo D, Costa E, Muñoz-Cobo B, Solano C, Remigia MJ et al. 401 Comparison of the new Abbott Real Time CMV assay and the Abbott CMV Page 19 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 19 402 PCR Kit for the quantitation of plasma cytomegalovirus DNAemia. Diagn 403 MicrobiolInfectDis 2013;75:207-209. 404 27. Gracia-Ahufinger I, Tormo N, Espigado I, Solano C, Urbano-Ispizua A, Clari 405 MA et al.Differences in cytomegalovirus plasma viral loads measured in 406 allogeneic hematopoietic stem cell transplant recipients using two commercial 407 real-time PCR assays. J Clin Virol 2010;48:142-146. 408 28. Solano C, Giménez E, Piñana JL, Vinuesa V, Poujois S, Zaragoza S et al. 409 Preemptive antiviral therapy for CMV infection in allogeneic stem cell 410 transplant recipients guided by the viral doubling time in the blood. Bone 411 MarrowTransplant2016;51:718-721. 412 29. Muñoz-Cobo B, Solano C, Costa E, Bravo D, Clari MÁ, Benet I et al. Dynamics 413 of cytomegalovirus (CMV) plasma DNAemia in initial and recurrent episodes of 414 active CMV infection in the allogeneic stem cell transplantation setting: 415 implications for designing preemptive antiviral therapy strategies. Biol Blood 416 Marrow Transplant 2011; 17:1602–1611. 417 30. Glucksberg H, Storb R, Fefer A, Buckner CD, Neiman PE, Clift RA et al. 418 Clinical manifestations of graft-versus-host disease in human recipients of 419 marrow from HL-A-matched sibling donors. Transplantation 1974;18:295-304. 420 31. Piñana JL, Perez-Pitarch A, Guglieri-Lopez B, Giménez E, Hernandez-Boluda 421 JC, Terol MJ et al. Sirolimus exposure and the occurrence of cytomegalovirus 422 DNAemia after allogeneic hematopoietic stem cell transplantation. Am J 423 Transplant 2018;18:2885-2894. Page 20 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 20 424 32. Crocchiolo R, Giordano L, Rimondo A, Bologna M, Sarina B, Morabito L, et al. 425 Human Herpesvirus 6 replication predicts Cytomegalovirus reactivation after 426 allogeneic stem cell transplantation from haploidentical donor. J ClinVirol. 427 2016;84:24-26. 428 33. Solano C, de la Cámara R, Vázquez L, López J, Giménez E, Navarro D 429 Cytomegalovirus Infection Management in Allogeneic Stem Cell Transplant 430 Recipients: a National Survey in Spain. J ClinMicrobiol 2015;53:2741-2744. 431 34. McCurdy SR, Luznik L Immune reconstitution after T-cell replete HLA- 432 haploidentical transplantation. SeminHematol 2019;56:221-222. 433 Author Contribution 434 David Navarro and Dixie Huntley developed the study idea. Maria Jesús Pascual, Juan 435 Carlos Hernández-Boluda, Beatriz Gago, Lourdes Vázquez, José Luis Piñana, Magdalena 436 García, Ariadna Pérez, David Serrano, Marta Hernández and Carlos Solano revised and 437 collected de data. Dixie Huntley and Estela Giménez performed the statistical analysis. 438 José Luis Piñana, Carlos Solano and Eliseo Albert supported the data interpretation. All 439 the coauthors revised the draft of the manuscript and David Navarro wrote the final 440 version of the manuscript. 441 Figure Legends 442 Figure 1. Cumulative incidence of CMV DNAemia through day 365 after transplantation 443 in patients undergoing different transplant modalities in whom plasma CMV DNA 444 monitoring was performed by means of the Abbott real time PCR assay (n=252). MRD 445 refers to matched related allo-HSCT and MUD to matched unrelated allo-HSCT. HLA- 446 mismatched includes allo-HSCTs with unrelated and related donors. Page 21 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review 21 447 Figure 2. Overall cumulative incidence of recurrent CMV DNAemia receiving 448 preemptive antiviral therapy (PET) through day 365 after transplantation in patients 449 undergoing different transplant modalities. MRD refers to matched related allo-HSCT 450 and MUD to matched unrelated allo-HSCT. HLA-mismatched includes allo-HSCTs with 451 unrelated and related donors. 452 Figure 3. Cumulative incidence of CMV DNAemia requiring preemptive antiviral 453 therapy (PET) through day 365 after transplantation in patients attended at Hospital 454 ClínicoUniversitario of Valencia undergoing different transplant modalities. At this 455 center PET was incepted when the plasma CMV DNA load reached levels of ≥1,500 456 IU/ml, or when the CMV doubling time (dt) was ≤2.0 days, whichever occurred first. 457 MRD refers to matched related allo-HSCT and MUD to matched unrelated allo-HSCT. 458 HLA-mismatched includes allo-HSCTs with unrelated and related donors. 459 Figure 4. Cumulative incidence of all-cause (overall) mortality by day 180 and by day 460 365 in patients undergoing different transplant modalities. MRD refers to matched related 461 allo-HSCT and MUD to matched unrelated allo-HSCT. HLA-mismatched includes allo- 462 HSCTs with unrelated and related donors. 463 464 465 466 467 Page 22 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Table 1. Patient demographics and clinical characteristics according to transplant modality. Parameter no. (%) Haploidentical (n=118) HLA mismatched (MMRD/MMUD) (n=27) MUD (n=62) MRD (n=76) Pvaluea Sex 0.34 Male 165 (58.3) 69 (59) 14 (52) 32 (52) 50 (66) Female 118 (41.7) 49 (41) 13 (48) 30 (48) 26 (34) Age (median, range) 55 (18-73) 58 (18-73) 50 (19-67) 55 (18- 70) 54 (18- 70) 0.59 Underlying disease 0.07 Acute leukemia 100 (35.3) 43 (36.4) 6 (22.2) 20 (32.3) 31 (40.8) Chronic leukemia 26 (9.2) 9 (7.6) 3 (11.1) 7 (11.3) 7 (9.2) Lymphoma 82 (29) 26 (22) 16 (59.3) 15 (24.2) 25 (32.9) MDS/ Multiple myeloma/Myelofibrosis 52 (18.4) 25 (21.2) 0 19 (30.6) 8 (10.5) Other 23 (8.1) 15 (12.7) 2 (7.4) 1 (1.6) 5 (6.6) Stem cell source <0.001 PB 258 (91.2) 110 (93.2) 19 (70.4) 57 (91.9) 72 (94.7) BM 18 (6.4) 8 (6.8) 3 (11.1) 3 (4.8) 4 (5.3) UCB 7 (2.5) 0 5 (18.5) 2 (3.2) 0 D/R CMV serostatus 0.001 Page 23 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review D+/R+ 162 (57.2) 73 (61.9) 12 (44.4) 24 (38.7) 53 (69.7) D−/R+ 84 (29.7) 30 (25.4) 10 (37) 31 (50) 13 (17.1) D+/R− 21 (7.4) 12 (10.2) 2 (7.4) 2 (3.2) 5 (6.6) D-R- 16 (5.7) 3 (2.5) 3 (11.1) 5 (8.1) 5 (6.6) Conditioning regimen 0.55 Myeloablative 81 (28.6) 35 (29.7) 10 (37) 14 (22.6) 22 (28.9) Reduced intensity 202 (71.4) 83 (70.3) 17 (63) 48 (77.4) 54 (71.1) Containing ATG 25 (8.8) 1 (0.8) 19 (70.4) 1 (1.6) 4 (5.3) <0.001 aGvHD prophylaxis <0.001 Based on Cyclosporin A 134 (47.3) 44 (37.3) 11 (40.7) 18 (29) 61 (80.3) Based on Tacrolimus 59 (20.8) 49 (41.5) 2 (7.4) 4 (6.5) 4 (5.3) Tacrolimus plus sirolimus 52 (18.4) 0 13 (48.1) 34 (54.8) 5 (6.6) Sirolimus/Mycophenolate Mophetil/ Cyclophosphamide 30 (10.6) 20 (16.9) 1 (3.7) 5 (8.1) 4 (5.3) Other combinations 8 (2.8) 5 (4.2) 0 1 (1.6) 2 (2.6) Acute GvHD 0.08 grades 0-I 195 (68.9) 73 (61.9) 23 (85.2) 45 (72.6) 54 (71.1) 0.08 grades II-IV 88 (31.1) 45 (38.1) 4 (14.8) 17 (27.4) 22 (28.9) Chronic GvHD 54 (19.1) 12 (10.2) 6 (22.2) 16 (25.8) 20 (26.3) 0.01 Page 24 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Treatment with corticosteroids>1mg- /kg/day 77 (27.2) 31 (26.3) 5 (18.5) 17 (27.4) 24 (31.6) 0.61 aStatistically significant (P<0.05). Abbreviations, ATG, Anti-thymocyte globulin; aGvHD, Acute Graft versus Host Disease; BM, Bone Marrow; CMV, Cytomegalovirus; D, Donor; HL, Hodgkin's Lymphoma; HLA, Human Leukocyte Antigen; MDS, Myelodysplastic Syndrome; MUD, Matched Unrelated Donor; MRD, Matched Related Donor; MMRD/MMUD, HLA mismatched related or unrelated; NHL, Non-Hodgkin's lymphoma; PB, Peripheral Blood; R, Receptor; UCB, Umbilical Cord Blood. Page 25 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Table 2. Analysis of potential risk factors for Cytomegalovirus DNAemia in patients undergoing Haploidentical transplantation. Univariate Factor HR (95% CI) Pvalueb Sex (male/ female) 1.13 (0.71- 1.79) 0.60 Age (< 65 years /> 65 years) 1.02 (0.58- 1.79) 0.96 Underlying disease Acute leukemia 0.85 (0.40- 1.81) 0.67 Chronic leukemia 1.73 (0.66- 4.48) 0.26 lymphoma 1.08 (0.49- 2.40) 0.84 MDS/MM/MF 0.74 (0.32- 1.70) 0.48 Other 1 (ref) Stem cell source PB / UCB plus BM 0.87 (0.38- 2.00) 0.74 D/R CMV serostatus R+ vs. R- 3.42 (1.25- 9.38) 0.02 D+ vs. D- 1.40 (0.82- 2.35) 0.23 D+ vs. D- in R+ 1.52 (0.89- 2.60) 0.13 Conditioning regimen Reduced intensity (Yes vs. No) 0.83 (0.51- 1.34) 0.44 aGvHD prophylaxis Page 26 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Based on Tacrolimus 0.78 (0.24- 2.57) 0.68 Based on Cyclosporin A 1.30 (0.40- 4.29) 0.66 Sirolimus/Mycophenolate Mophetil/ Cyclophosphamide 1.71 (0.50- 5.87) 0.40 Other 1 (ref) aGvHDa 0-I/ vs II-IV 0.65 (0.37- 1.14) 0.13 aTime dependent covariate bStatistically significant (P<0.05). Abbreviations,aGvHD, Acute Graft versus Host Disease; BM, Bone Marrow;CMV, Cytomegalovirus; D, Donor; HL, Hodgkin's Lymphoma; MDS, Myelodispastic Syndrome; NHL, Non-hodgkin's lymphoma; PB, Peripheral Blood; R, Receptor; UCB, Umilical Cord Blood. Page 27 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Table 3. Virological features of initial episodes of Cytomegalovirus DNAemia according to the modality of allogeneic hematopoietic stem cell transplantation Factor Haploidentical HLA mismatched (MMRD/MMUD) MUD MRD P value Patients monitored with the Abbott real-time PCR assay Initial CMV DNA load (IU/ml) median (range)a 114 (30-8,705) 80 (31-402) 104 (31- 66,717) 107 (33- 9,711) 0.79 All patients Days to CMV DNAemia, median (range)b 32 (-7-123) 30 (-2-126) 30 (-8- 204) 26 (-7- 166) 0.35 CMV doubling time, median (range)c 1.97 (0.76- 3.66) 2.12 (0.82-3.86) 2.48 (0.57- 6.76) 2.32 (0.44- 5.60) 0.08 CMV DNA half life following antiviral preemptive therapyb 3.23 (0.95- 34.8) 2.64 (0.33-6.25) 3.57 (0.66- 20.5) 2.22(0.36- 15.5) 0.49 Patients undergoing allo-HSCT at HCUV CMV peak load (IU/ml), 4,324 (133- 4,268,946) 1,883 (56-14,467) 847 (47- 62466) 1,182 (66- 122,547) 0.007 Page 28 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review median (range)d Duration in days, median (range)d 49 (7-192) 28 (7-134) 42 (7- 162) 42 (3-158) 0.30 CMV DNA half life for non-treated episodese 2.87 (0.95- 34.8) 2.49 (0.33-6.25) 3.57 (0.81- 20.5) 2.24 (0.36- 15.5) 0.98 aFrom 252 patients monitored with the Abbott RealTime CMV PCR to avoid a potential bias related to the different performance of this and the Affigene PCR assays27. bAll patients experiencing CMV DNAemia (n=200). As for the CMV DNA half life, the CMV DNA peak is taken as CMV DNA load at t0 irrespective of whether or not antiviral treatment has begun29. cCalculated from a total 109 episodes meeting the criteria stated in the methods section and developing in patients attended at all participating centers (both PCRs are collinear and dts are calculated in the absence of antiviral therapy28) dOnly patients (n=199) undergoing allo-HSCT at HCUV were included, as the duration and the CMV DNA peak load of a given episode are dependent upon the CMV DNA load at which preemptive antiviral therapy is initiated29 (different across institutions). eOnly patients (n=72) undergoing allo-HSCT at HCUV were considered, since there was not sufficient number (or simply there was not) of untreated episodes across transplant types in the remaining participating centers. Abbreviations, CMV, Cytomegalovirus; dt, doubling time; HLA, Human Leukocyte Antigen; MMRD/MMUD, HLA mismatched related or unrelated; MUD, Matched Unrelated Donor; MRD, Matched Related Donor. Page 29 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Table 4. Virological characteristics of patients developing CMV disease within the study period Patie nt numb er CMV D/R serostat us Days to CMV DNAemia following transplantat ion Initial CMV DNA load (IU/m l) Preempt ive antiviral therapy CMV peak load (IU/ml) Duratio n of CMV DNAe mia (days) CMV DNA dt (days) 13 D+/R+ 34 240 Yes 671 15 Not calculat eda 23 D+/R+ No CMV DNAemia - No - - - 53 D-/R+ -1 <150 No <150 7 Not calculat eda 132 D+/R+ 7 34 Yes 26,941 152 2.06 180 D-/R+ 53 47 Yes 4,268,9 46 86 Not calculat eda CMV, Cytomegalovirus; D, Donor; dt, doubling time; IU, International Units; R, Recipient. aIncrease between the first and second CMV DNA load values of ≤3-fold. Page 30 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Figure 1 133x85mm (300 x 300 DPI) Page 31 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Figure 2 revised 148x85mm (300 x 300 DPI) Page 32 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Figure 3 193x266mm (300 x 300 DPI) Page 33 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Figure 4 283x212mm (300 x 300 DPI) Page 34 of 34Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 For Review Supplementary Table 1. Causes of one-year overall mortality in patients undergoing different transplant modalities. Cause no. (%) HLA mismatched Haploidentical MUD MRD P value Infectious complications 16 (21.6) 1 (20) 7 (20) 4 (30.8) 4 (22.2) 0.65 Relapse 14 (18.9) 1 (20) 8 (22.9) 0 5 (27.8) Pneumonia 9 (12.2) 1 (20) 3 (8.6) 2 (15.4) 3 (16.7) GvHD 6 (8.1) 0 2 (5.7) 0 4 (22.2) Graft failure 1 (1.4) 0 1 (2.9) 0 0 GvHD plus infectious complications 2 (2.7) 0 1 (2.9) 1 (7.7) 0 CMV disease 1 (1.4) 0 1 (2.9) 0 0 Other causesa 25 ( 33.8) 5 (62.5) 12 (34.3) 6 (46.2) 2 (11.1) Total 74 (26.1) 8 35 13 18 aIncluding cardiac tamponade, diffuse leukoencephalopathy, sinusoidal obstruction syndrome, severe acute liver failure, intraventricular haemorrhage, among other causes Abbreviations. GvHD, Graft versus Host Disease; HLA, Human Leukocyte Antigen; MUD, Matched Unrelated Donor; MRD, Matched Related Donor. Page 35 of 34 Transplant Infectious Disease 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60