Open access Protocol Efficacy and safety of the combination of reduced duration prophylaxis followed by immuno-guided prophylaxis to prevent cytomegalovirus disease in lung transplant recipients (CYTOCOR STUDY): an open-label, randomised, non-inferiority clinical trial Aurora Paez-Vega,1,2 Sara Cantisan,1,2,3 José Manuel Vaquero,4 Elisa Vidal,1,2,3 Antonio Luque-Pineda,5 María Ángeles Lobo-Acosta,6 Ana Belén Pérez,‍ ‍ 1,7 Rodrigo Alonso-Moralejo,8 David Iturbe,9 Victor Monforte,10,11 Isabel Otero-Gonzalez,12 Amparo Pastor,‍ ‍ 13 Piedad Ussetti,14 Julian Torre-Cisneros1,2,3 To cite: Paez-Vega A, Abstract Cantisan S, Vaquero JM, Strengths and limitations of this study Introduction Prolonged use of antivirals to prevent the et al. Efficacy and safety of development of cytomegalovirus (CMV) disease in lung the combination of reduced ►► If the hypothesis of this clinical trial is confirmed, transplant patients has been shown to have significant the usual clinical practice for the management of duration prophylaxis followed by immuno-guided prophylaxis side effects, for which alternatives are being sought to cytomegalovirus (CMV) in lung transplant recipients to prevent cytomegalovirus reduce their use. The monitoring of cell immunity against could be modified by incorporating the monitoring disease in lung transplant CMV could be an alternative as it has shown to be useful of specific cell immunity against this virus, which recipients (CYTOCOR in identifying transplant patients at low risk of infection, would allow for the better identification of patients STUDY): an open-label, who could benefit from shorter prophylaxis. The aim of the at risk of CMV disease. randomised, non-inferiority CYTOCOR study is to demonstrate that the combination ►► It would also reduce the time of antiviral prophylaxis clinical trial. BMJ Open of a reduced prophylaxis strategy with subsequent CMV- 2019;9:e030648. doi:10.1136/ in many of these patients with CMV-specific immu- specific immunological monitoring would allow CMV nity and therefore prevent or limit the adverse ef- bmjopen-2019-030648 infection to be controlled in lung transplant patients as fects of this antiviral and lead to economic savings. ►► Prepublication history for effectively as the usual strategy (prophylaxis followed by ►► The main limitation of this study is the complexity this paper is available online. pre-emptive therapy), while reducing the side effects of of the design of the clinical trials, which can hinder To view these files, please visit antivirals due to the shorter duration of prophylaxis. the journal online (http://​dx.​doi.​ the inclusion and follow-up of candidates. For this Methods and analysis Phase III randomised, open, reason, a sample size has been calculated assuming org/​10.​1136/​bmjopen-​2019-​ 030648). multicentre, parallel, non-inferiority clinical trial to study a 5% loss to follow-up and a conservative inclusion the efficacy and safety of the combination of a prophylaxis rate in the estimated time. Received 25 March 2019 strategy up to month +3 post-transplant followed by ►► Another limitation is the QuantiFERON-CMV tech- Revised 12 July 2019 immuno-guided prophylaxis using the QuantiFERON-CMV nique, as this technique only measures CD8 +spe- Accepted 22 July 2019 technique up to month +12 post-transplant to prevent CMV cific T-cell response and does not cover patients disease in CMV-seropositive lung transplant recipients. with rare human leucocyte antigen class I alleles. This strategy will be compared with a combination of a © Author(s) (or their usual prophylaxis strategy up to month +6 post-transplant employer(s)) 2019. Re-use followed by pre-emptive therapy up to month +12. To permitted under CC BY-NC. No study the incidence of CMV disease, patients will be by increasing knowledge about the safety and efficacy of commercial re-use. See rights followed up to 18 months post-transplantation. A total of discontinuing valganciclovir prophylaxis in lung transplant and permissions. Published by 150 patients are expected to be recruited for the study. recipients. BMJ. Trial registration number NCT03699254. Ethics and public dissemination The clinical trial has For numbered affiliations see been approved by the Research Ethics Committees and end of article. Introduction authorised by the Spanish Agency of Medicines and Correspondence to Medical Devices (AEMPS). Cytomegalovirus (CMV) infection is a signifi- Dr Sara Cantisan; If the hypothesis of this clinical trial is verified, the cant cause of morbidity and mortality in solid ​sacanti@​hotmail.​com dissemination of the results could change clinical practice organ transplant (SOT) patients. The risk of Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 1 Open access CMV disease in SOT patients depends on several factors, prophylaxis for 5 months or experimental prophylaxis among others the transplanted organ, the donor/recip- guided by QF-CMV. The authors observed that the ient CMV serology and the immunosuppression therapy QF-CMV-guided experimental prophylaxis arm had a used.1 2 lower incidence of CMV infection than the standard Depending on each patient’s risk, the prevention prophylaxis arm. Therefore, the standardisation and vali- strategy to be used is defined. There are two types of strat- dation of these studies have the potential to significantly egies: universal prophylaxis and pre-emptive treatment. change the monitoring and treatment of CMV infection Universal prophylaxis consists of the administration of in transplanted patients and further individualise strate- antivirals such as ganciclovir or valganciclovir during the gies to prevent CMV infection.20 21 first months post-transplant. Pre-emptive therapy is based Bearing in mind these results, we have formulated a new on the administration of antivirals once the CMV repli- hypothesis based on the fact that lung transplant patients cation has been detected in blood or serum, for which it who are QF-CMV Reactive at month +3 after transplanta- is necessary to monitor the patient at regular intervals.2 3 tion could benefit from reduced duration prophylaxis, as In the particular case of lung transplant recipients, they have specific immunity to maintain the virus under both the international and Spanish consensus guidelines control. Thus, by combining a strategy of reduced dura- on the management of CMV infection in SOT patients tion prophylaxis (henceforth reduced prophylaxis) with recommend universal prophylaxis in all lung transplant immunological monitoring of CMV-specific response recipients of a CMV-positive donor, with the serology of at a later stage would control CMV replication in these the recipient determining the duration of prophylaxis: patients in the same way as the current strategy (prophy- 12 months in CMV-negative recipients (D+/R-) and 6 laxis followed by pre-emptive therapy), while reducing months in CMV-positive recipients (D+/R+).1 2 the side effects of antivirals since the duration of prophy- However, the application of universal prophylaxis has laxis is shorter. The aims of CYTOCOR study are: (1) To associated risks due to the side effects of prolonged anti- evaluate the efficacy of reduced prophylaxis (3 months) viral use. The most frequent side effects are leucopenia, followed by immuno-guided prophylaxis (QF-CMV digestive discomfort (diarrhoea, vomiting, abdominal Reactive, cut-off 0.2 IU/mL) to prevent CMV disease pain) and renal dysfunction. To prevent or reduce the in R+lung transplant recipients in comparison with adverse effects of these antivirals, recent research has the usual strategy of universal prophylaxis (6 months) focused on the search for immunological biomarkers followed by pre-emptive therapy for 6 months and (2) To to help identify transplant patients at low risk of CMV assess whether, in the patients of experimental group who replication/reactivation in which prophylaxis could be develop CMV disease, an IFNG cut-off point other than reduced or even discontinued. In particular, the moni- 0.2 IU/mL could predict protection against the disease toring of cell-mediated CMV immunity has been shown more reliably. to be useful in guiding clinical decision-making in trans- planted patients.3–8 Several techniques are currently available to monitor Methods and analysis cell-mediated immunity to CMV, including the use of Design multimers, intracellular staining, Enzyme-Linked Immu- This is a phase III randomised, open, multicenter, parallel, nospot assay (ELISPOT) and QuantiFERON-CMV assay non-inferiority clinical trial. The patients will be assigned (QF-CMV). Regardless of the technique used, several to two groups (figure 1): authors have shown that the presence of cellular immu- 1. Control Group (universal prophylaxis+pre-emptive nity to CMV in pre-transplantation or post-transplantation therapy; 6+6): In this patients the recommendation is associated with a lower risk of CMV replication and/or of the Spanish Consensus Document1 will be followed disease.9–18 Specifically, our group has been working for according to this strategy: (i) universal prophylaxis with years in the pre-transplant monitoring of cell immunity valganciclovir (900 mg/24 hours, corrected for renal against CMV in SOT patients using the QF-CMV tech- function) up to month +6. The use of associated immu- nique (Qiagen). This is a functional technique that quan- notherapy (eg, anti-CMV hyperimmune immunoglob- tifies interferon-γ (IFNG) released by CMV-specific CD8 ulin) will depend on each centre’s clinical practice; +T cells when stimulated with 22 CMV peptides.16 19 Our (ii) pre-emptive therapy guided by viral load from month published results indicate that patients with CMV-spe- +6 to month +12. For a viral load above >38 copies/mL cific cell response (QF-CMV Reactive; ≥0.2 IFNG IU/mL) (>35 IU/mL) and depending on each centre’s clinical prior to transplantation have a lower risk of CMV replica- practice, treatment with valganciclovir may be initiated tion after transplantation.16 (900 mg/12 hours, corrected for renal function). Blips Recently published results of a clinical trial in lung must be excluded before starting treatment. transplant recipients have shown that the monitoring of 2. Experimental Group (reduced prophylaxis+immu- CMV-specific cell immunity, also measured by QF-CMV, no-guided prophylaxis; 3+9): (i) universal prophylaxis permits individualising the preventive management with valganciclovir (900 mg/24 hours, corrected for of CMV disease in these transplant recipients.20 The renal function) up to month +3. The use of associated patients in the study were randomised to receive standard immunotherapy (eg, anti-CMV hyperimmune immu- 2 Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 Open access Figure 1 Flow diagram. CMV,cytomegalovirus; QF-CMV, QuantiFERON-CMV. noglobulin) will depend on each centre’s clinical prac- usual clinical practice, ganciclovir may be used (5 mg/ tice; (ii) immuno-guided prophylaxis. This will consist of kg/12 hours, corrected for renal function). All patients a monthly determination of cellular immunity by QF- will be followed up to month +18 post-transplant to study CMV from month +3 to month +12. In this group, the CMV disease. strategy will be as follows (figure 2): 1. Following the first determination of positive specific Study population and setting immunity (QF-CMV Reactive), prophylaxis will be The clinical trial is a multicentre project in which seven discontinued. Monthly monitoring of the specific national lung transplant centres will participate. The trial immunity will continue until month +12. Cases in will include lung transplant patients with positive CMV which the specific immunity is negative (QF-CMV serology belonging to the participating centres. Patients Non-Reactive or Indeterminate) after initiating im- who meet all the inclusion criteria and no exclusion muno-guided prophylaxis, valganciclovir prophy- criteria will be prospectively included in the study. laxis will be resumed. The inclusion and exclusion criteria for the trial are 2. In patients in whom all cell immunity determi- described in box 1. nations are negative (QF-CMV Non-Reactive or Indeterminate), valganciclovir prophylaxis will be Withdrawal criteria maintained until month +12. Patients may withdraw from the study at any time, for any 3. At least one viral replication control will be per- reason and without prejudice to future medical treat- formed with each cell immunity determination ment. Patients who do not comply with the study proce- (monthly) and if positive (>38 copies/mL or dure, have not been followed up or for whom no further >35 IU/mL), will be treated according to each cen- information has become available since the date of with- tre’s clinical practice. drawal or the date of last contact shall be considered a 4. If the patient in the experimental group continues study “withdrawal”. The reasons for withdrawal will be with prophylaxis at month +12, the prophylaxis examined in full accordance with bioethical principles should be discontinued at this time. regarding the guarantee of patients’ rights and autono- In either of the two groups (control and experi- mous and informed consent. The criteria for withdrawal mental) and when indicated according to each centre’s from the study are described below: Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 3 Open access Figure 2 Study design. m, month; PCR, polymerase chain reaction. 1. On patient’s request and withdrawal of patient’s in- 7. Unexpected serious adverse reaction at the discretion formed consent. of the researcher. 2. Protocol violation or deviation. 8. The endpoint of the study is reached: 3. If considered clinically appropriate by the investigators –– In the experimental group (3+9): Loss to fol- when the patient’s symptoms worsen. low-up/Death/QF-CMV Non-reactive at month 4. Administrative decision by investigators, sponsor or a +12. regulatory authority. –– In the control group (6+6): Loss to follow-up/ 5. Loss to follow-up. 6. Serious adverse event or clinically relevant event at the Death/CMV replication at month +12. discretion of the researcher. The investigator shall indicate whether the patient or the investigator made the decision to withdraw from the study and which of the following possible reasons led to Box 1 Study selection criteria the withdrawal: 1. Any patient in either group who develops CMV disease Inclusion criteria (symptomatic replication or organ disease without 1. Lung transplant recipients with positive pre-transplant CMV serology viraemia) will be withdrawn from the study (patients 2. Over 18 years of age 3. That the expected time of prophylaxis with valganciclovir is 6 who develop asymptomatic replication will not be months post-transplant withdrawn from the study; they will be treated and the 4. Patients who have given written informed consent scheduled follow-up will continue). Exclusion criteria 2. On patient’s request and withdrawal of informed con- 1. Pre-transplant CMV-seronegative recipients sent. 2. HIV-infected patients 3. Protocol violation or deviation (eg, non-compliance 3. Pregnant and/or lactating women with treatment, need for prohibited treatment, etc). 4. Intolerance to valganciclovir/ganciclovir 4. If considered clinically appropriate by the investigators 5. Multivisceral transplant patients 6. Patients who cannot comply with the follow-up protocol when the patient’s medical condition worsens. 5. Administrative decision by investigators, sponsor or a CMV, cytomegalovirus. regulatory authority. 4 Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 Open access doses required or reduction in immune suppression on Table 1 Definitions included in the study the basis of low white blood cells/neutrophil count). Type Definition CMV replication Can be diagnosed by growing Randomisation and masking the virus in vitro, finding The number of patients will be 150 (75 in each evidence of viral infection by group). Patients who meet the selection criteria will be intra-cytoplasmic or intra-nuclear randomised, and may be included in the control group or inclusions or by antibody-based the experimental group. Randomisation will be carried staining techniques for CMV in out by means of electronic case report forms (eCRFs). histopathological sections or finding evidence of replication The ratio will be 1:1 for each group and stratified by using nucleic acid based assays centres. The study design is open, but the investigator or antigenaemia studies. will not know the treatment assignment until the patient CMV disease Evidence of CMV infection with signs the informed consent form and randomisation is attributable symptoms. CMV performed, thus minimising selection bias. disease can be sub-classified into CMV viral syndrome or Study procedures tissue invasive disease. The duration of follow-up for each patient will be 18 Definitive diagnosis of CMV months and will start from the moment the patient is pneumonia must be based on transplanted. A total of 15 visits will be scheduled during the histological demonstration of CMV invasive disease. the trial: one visit during the first 30 days post-transplant, Nevertheless, for this study we 12 monthly visits up to the first 12 months post-trans- also accept the evidence of CMV plant, one visit at 15 months post-transplant and one visit infection (including detection of at 18 months post-transplant. The follow-up visits in the CMV-DNA in bronchoalveolar Control and Experimental groups will be scheduled as lavage (BAL)) with attributable they are shown in tables 2 and 3, respectively. All visits symptoms once other potential may be made 7 days before or after the day indicated by causes has been ruled out. the protocol without being considered deviation, as they CMV, cytomegalovirus. will coincide with the visits made following usual clinical practice. Both groups: As for determination of CMV replication, in the first 3 months it will not be compulsory to monitor viral Study variables replication (unless indicated according to the centre’s Efficacy variables clinical practice) nor will CMV-specific cell immunity be 1. Primary outcome variable: Incidence of CMV disease determined because both groups are receiving universal at 18 months post-transplant. “CMV disease” is defined prophylaxis. It will only be compulsory to draw a sample as evidence of CMV infection with attributable symp- for CMV viral load in patients in which prophylaxis has toms (table 1). CMV disease can be sub-classified as been discontinued. The first determination of CMV viral CMV viral syndrome or invasive tissue disease.2 load will coincide with the day prophylaxis is discontinued 2. Secondary outcome variables: Incidence of CMV rep- and taken as a baseline determination. In centres where lication (excluding replication blips in periods of pro- CMV viraemia is monitored by antigenaemia assay or the phylaxis). “CMV replication” is defined as a viral load viral load is determined in whole blood, an aliquot should greater than 38 copies/mL (equivalent to approxi- be sent to the laboratory of the coordinating centre to mately 35 IU/mL)(table 1).2 determine the CMV viral load. Experimental group: To determine the CMV-specific cell Explanatory variables immunity, all the samples will be sent to the laboratory of The following demographic and clinical information will the coordinating centre for analysis. Depending on the be collected from all the patients: age, sex and baseline results, the following procedures will be performed: (a) If disease, type of transplant (single lung or double lung), the QF-CMV is Reactive (IFNG ≥0.2 UI/mL) at any of these pre-transplant CMV serology, donor and recipient HLA visits, valganciclovir prophylaxis will be discontinued; typing, induction immunosuppressive therapy (dose and (b) If the QF-CMV is Non-Reactive (IFNG <0.2 IU/mL), duration), maintenance immunosuppressive therapy prophylaxis will be continued (or reinitiated if previously (dose and duration), CMV antiviral treatment (dose and discontinued) and (c) In those cases in which the patient duration, including immunotherapy), other opportu- of the experimental group is on prophylaxis until month nistic infections not associated with CMV (bacterial, viral +12, prophylaxis will be discontinued. and fungal), acute or chronic graft rejection (time since transplantation, number of episodes and treatment) and Statistical analysis adverse effects attributable to CMV antiviral treatment The required sample size for a non-inferiority trial has (total number of granulocyte-colony stimulating factor been calculated assuming an 85% success rate of the Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 5 Open access Table 2 Summary chart of visits (control group) Procedures Visit 1 Visit 2 to Visit 7 Visit 8 to Visit 13 Visit 14 and Visit 15 control group (first 30 days) (month +1 to+6) (month +7 to +12) (month +15 and +18) Informed consent X Inclusion/exclusion criteria X Randomisation X Medical history/anamnesis X X X X Physical examination* X X X X Pregnancy test X Antiviral prophylaxis X X † CMV PCR sample X X ‡ Haemogram/biochemistry X X X X Adverse events/concomitant X X X X medication *Physical examination: weight, heart rate, blood pressure, temperature, abdominal palpation and presence of oedemas †CMV PCR will be compulsory when antiviral prophylaxis is discontinued. The first CMV PCR will be performed at Visit 7 (month +6), coinciding with the discontinuation of antiviral prophylaxis. At Visits 14 and 15 it will not be compulsory to draw samples for viral load (unless indicated according to the center’s clinical practice). ‡Haemogram: red blood cells, haemoglobin, leukocytes, neutrophils and platelets. Biochemistry: alkaline phosphatase, gamma- glutamyltransferase, alanine aminotransferase, aspartate aminotransferase, C-reactive protein, bilirubin, albumin and creatinine. CMV, cytomegalovirus; PCR, polymerase chain reaction. control group, a non-inferiority margin of 7%, an alpha the experimental regimen is not less effective than the risk of 0.05, a power of 80% (beta risk 0.20) and an esti- control regimen (non-inferiority study) in terms of the mated follow-up loss of 5%. The total number of patients incidence of CMV disease in the 18 months post-trans- required per group is 75 (total sample of 150 patients).22 plant (primary endpoint). The sample size was determined in order to address Clinical data will be collected by means of eCRFs. All the primary objective of the study, that is, to evaluate if analyses will be performed using PASW Statistics software Table 3 Summary chart of visits (experimental group) Procedures Visit 1 Visit 2 to Visit 3 Visit 4 to Visit 13 Visit 14 and Visit 15 experimental group (first 30 days) (month +1 to +2) (month +3 to +12) (month +15 and +18) Informed consent X Inclusion/exclusion criteria X Randomisation X Medical history/anamnesis X X X X Physical examination* X X X X Pregnancy test X † Antiviral prophylaxis X X X CMV PCR ‡,§ X X QF-CMV sample§ X Haemogram/biochemistry¶ X X X X Adverse events/concomitant X X X X medication *Physical examination: weight, heart rate, blood pressure, temperature, abdominal palpation and presence of edemas †In month +3 post-transplant, the patient will continue with antiviral prophylaxis depending on the QF-CMV results. ‡CMV PCR will be compulsory when antiviral prophylaxis is discontinued. The first CMV PCR will coincide with the day prophylaxis is discontinued and will be taken as a baseline determination. §At Visits 14 and 15 it will not be compulsory to draw samples for viral load or for QF-CMV (unless indicated according to the center’s clinical practice) ¶Haemogram: red blood cells, haemoglobin, leukocytes, neutrophils and platelets. Biochemistry: alkaline phosphatase, gamma- glutamyltransferase, alanine aminotransferase, aspartate aminotransferase, C-reactive protein, bilirubin, albumin and creatinin CMV, cytomegalovirus; PCR, polymerase chain reaction; QF-CMV, QuantiFERON-CMV. 6 Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 Open access V.15.0 (IBM Corporation) and R software (V.3.5.0). In the particular case of lung transplant patients, the Frequencies and percentages will be calculated for the results of the first clinical trial in these patients in which qualitative variables and compared using the X2 test or immunological monitoring is used to individualise the Fisher’s test. For quantitative variables, the mean and duration of universal prophylaxis have recently been SD will be calculated. Normality will be analysed using published.20 In this study, patients in the arm with exper- the Kolmogorov-Smirnov test and comparisons will be imental prophylaxis immuno-guided by QF-CMV showed made using the Student’s t-test or the Mann-Whitney a lower incidence of CMV infection than in the arm with test depending on whether or not they follow a normal standard prophylaxis for a duration of 5 months. distribution, respectively. For the comparison of three or However, if the hypothesis of our study is confirmed, more groups, the analysis of variance (ANOVA) or Krus- the duration of CMV antiviral prophylaxis in lung trans- kal-Wallis tests will be performed. The incidence of CMV plant patients could be further shortened, as it could be disease according to the strategy used will be calculated reduced to only 3 months in patients who already present by Kaplan-Meier curves which will be compared using the specific CMV-specific immunity at 3 months. This would log-rank test. If patients in the Experimental Group (3+9) reduce the toxicity associated with the prolonged use of develop CMV disease, a multivariate Cox proportional antivirals and lead to greater economic savings of antiviral hazards regression model will be used. The Receiver drugs. Operating Characteristic (ROC) curve will be used to On the other hand, there is scientific evidence of late- calculate if there is a cut-off in IFNG levels other than 0.2 onset CMV disease at 12 months after lung transplanta- UI/mL that could better predict protection against CMV tion.23 Therefore, our study could prove whether in the disease. subgroup of patients who reach month +12 without cell immunity to the virus (QF-CMV Non-Reactive) have a higher incidence of late CMV disease. These results would Ethical issues and dissemination plan serve to evaluate the possibility of prolonging prophylaxis This clinical trial will be conducted in accordance with antivirals in this small subgroup of patients. with the protocol, the principles set out in the current As for the technique we intend to use to monitor cell revised version of the Declaration of Helsinki (Fortaleza, immunity against CMV in our study population, we have 2013) and in accordance with the applicable regulatory chosen QF-CMV because it is a standardised technique requirements, in particular the ICH Tripartite Guide- with a well-defined cut-off, requires minimal sample line “Standards of Good Clinical Practice”, Royal Decree manipulation, is easy to use, provides negative and posi- 1090/2015 regulating clinical trials with medicinal prod- tive controls for each patient and is automatable. Addi- ucts in Spain, and Regulation (EU) No 536/2014 of the tionally, our group has used this technique for years and European Parliament and of the Council of 16 April 2014 we therefore have broad experience and a highly quali- on clinical trials on medicinal products for human use. fied staff. The protocol, the informed consent form, the patient In conclusion, the CYTOCOR study aims to individu- information form and any documents applicable to the alise the management of CMV infection in lung trans- study have required approval by the appropriate regula- plant patients by monitoring CMV-specific immunity. If tory agencies. The study has been approved by the Coor- our hypothesis is confirmed, the management of CMV dinating Committee for Biomedical Research Ethics. infection in lung transplant patients could be individu- Authorisation has also been obtained from the Spanish alised in such a way that: (1) The toxicity associated with Agency of Medicines and Medical Devices (AEMPS). the prolonged use of antivirals would be reduced, (2) The trial is registered in publicly accessible databases Economic costs would be reduced by decreasing the anti- such as the Spanish Clinical Studies Registry (REec) and​ viral treatment, (3) Costs of virological monitoring would ClinicalTrials.​gov (NCT03699254). be saved and (4) Morbidity and costs associated with late disease would be saved after inadequate discontinuation of prophylaxis in these patients. Discussion Immunological monitoring of CMV infection in trans- Author affiliations 1 planted patients has been shown to be useful in identi- Infectious Diseases Group, Instituto Maimónides de Investigación Biomédica de fying patients who are protected against infection by the Córdoba (IMIBIC)/Reina Sofía University Hospital/University of Cordoba, Cordoba, Spain virus after transplantation and in whom antiviral treat- 2 Spanish Network for Research in Infectious Diseases (REIPI, RD16/0016/0008), ment may be reduced or discontinued. However, the Instituto de Salud Carlos III, Madrid, Spain vast majority of studies that have addressed this issue are 3 Infectious Diseases Unit, Reina Sofía University Hospital, Cordoba, Spain observational,4–19 and do not provide solid evidence that is 4 Thoracic Surgery and Lung Transplantation Unit, Reina Sofía University Hospital, strong enough for rapid implementation in routine clin- Cordoba, Spain 5 Clinical Trial Unit, Instituto Maimónides de Investigación Biomédica de ical practice. It is therefore a major challenge to perform Córdoba (IMIBIC)/Reina Sofía University Hospital/University of Córdoba (SCReN intervention studies to demonstrate that the monitoring PT17/0017/0032), Cordoba, Spain of cell immunity against CMV in transplanted patients is a 6 Clinical Trial Unit, Virgen del Rocío University Hospital (CTU-HUVR), very useful in routine clinical practice. (SCReNPT13/0002/0010-PT17/0017/0012), Sevilla, Spain Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648 7 Open access 7 Microbiology Unit, Reina Sofía University Hospital, Cordoba, Spain 3. Egli A, Humar A, Kumar D, et al. State-Of-The-Art monitoring 8 Neumology Service, Instituto de Investigación i+12 Hospital Universitario 12 de of cytomegalovirus-specific cell-mediated immunity after organ Octubre. (REIPI, RD16/0016/0002), Madrid, Spain transplant: a primer for the clinician. Clin Infect Dis 2012;55:1678–89. 9 4. Manuel O, Husain S, Kumar D, et al. Assessment of cytomegalovirus- Neumology Service, University Hospital Marqués de Valdecilla-IDIVAL (REIPI, specific cell-mediated immunity for the prediction of cytomegalovirus RD16/0016/0007), Santander, Spain disease in high-risk solid-organ transplant recipients: a multicenter 10 Respiratory Department, Vall d' Hebron Barcelona Hospital Campus. Universitat cohort study. Clinical Infectious Diseases 2013;56:817–24. Autónoma de Barcelona, (REIPI, RD16/0016/0003), Barcelona, Spain 5. Lisboa LF, Kumar D, Wilson LE, et al. Clinical utility of 11 Ciber Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, cytomegalovirus cell-mediated immunity in transplant recipients with Spain cytomegalovirus viremia. Transplantation 2012;93:195–200. 12 6. Kumar D, Chernenko S, Moussa G, et al. Cell-Mediated immunity to Neumology Service, Instituto de Investigación Biomédica de A Coruña (INIBIC), predict cytomegalovirus disease in high-risk solid organ transplant Complejo Hospitalario Universitario de A Coruña (CHUAC) Sergas Universidade da recipients. Am J Transplant 2009;9:1214–22. Coruña (UDC), (REIPI, RD16/0016/0006), As Xubias, A Coruna, Spain 7. Fernández-Ruiz M, Kumar D, Humar A. Clinical immune-monitoring 13 Lung Transplant Unit, La Fe University and Polytechnic Hospital, Valencia, Spain strategies for predicting infection risk in solid organ transplantation. 14 Neumology Service, Puerta de Hierro-Majadahonda University Hospital, Clin Transl Immunology 2014;3:e12. Majadahonda, Spain 8. Calarota SA, Aberle JH, Puchhammer-Stöckl E, et al. Approaches for monitoring of non virus-specific and virus-specific T-cell response in solid organ transplantation and their clinical applications. J Clin Virol Acknowledgements Other members of the CYTOCOR project team: Francisco 2015;70:109–19. Santos, Javier Redel, Irene Gracia, José Carlos Garrido and Ana Salinas (Reina 9. Sester M, Sester U, Gärtner B, et al. Levels of virus-specific Sofía University Hospital). We would like to acknowledge the support of the Spanish CD4 T cells correlate with cytomegalovirus control and predict Network for Research in Infectious Disease (REIPI, RD16/0016), the Group for the virus-induced disease after renal transplantation. Transplantation Study of Infections in Transplant Recipients (GESITRA) of the Spanish Society of 2001;71:1287–94. 10. Sester U, Gärtner BC, Wilkens H, et al. Differences in CMV- Infectious Diseases and Clinical Microbiology (SEIMC) and SCReN (Spanish Clinical specific T-cell levels and long-term susceptibility to CMV infection Research Network) funded by the ISCIII-Sub-Directorate General for Research after kidney, heart and lung transplantation. Am J Transplant Assessment and Promotion through project PT13/0002/0010-PT17/0017/0012 and 2005;5:1483–9. PT17/0017/0032. 11. López-Oliva MO, Martínez V, Buitrago A, Buitrago Águeda, et al. Pretransplant CD8 T-cell response to ie-1 discriminates seropositive Contributors JT-C, AP-V, SC and JMV were responsible for formulating the kidney recipients at risk of developing CMV infection posttransplant. research question, the methodological design of the study and writing the first Transplantation 2014;97:839–45. draft of the manuscript. JT-C, AP-V and SC were responsible for obtaining financial 12. Abate D, Saldan A, Fiscon M, et al. Evaluation of cytomegalovirus support for the study. EV and ABP revised the statistical analysis plan and the (CMV)-specific T cell immune reconstitution revealed that baseline methodological aspects of the study. JT-C, AP-V and JMV collaborated in the antiviral immunity, prophylaxis, or preemptive therapy but not selection of the hospitals participating in the study. AL-P and MAL-A drafted the antithymocyte globulin treatment contribute to CMV-specific T drug safety surveillance portion of the study. JT-C is the coordinating investigator. cell reconstitution in kidney transplant recipients. J Infect Dis PU, RA-M, AP, IO-G, VM and DI have collaborated in the critical revision of the 2010;202:585–94. manuscript. All authors have read and approved the final manuscript. 13. Abate D, Saldan A, Mengoli C, et al. Comparison of cytomegalovirus (CMV) enzyme-linked immunosorbent spot and CMV Funding The authors have not declared a specific grant for this research from any quantiferongammainterferon-releasing assays in assessing risk funding agency in the public, commercial or not-for-profit sectors. of CMV infection in kidney transplant recipients. JClinMicrobiol 2013;51:2501–7. Competing interests J.T.C. and S.C. have received an unrestricted research grant 14. Costa C, Astegiano S, Terlizzi ME, et al. Evaluation and significance from Roche Pharma and Qiagen. They have also received payments from Qiagen for of cytomegalovirus-specific cellular immune response in lung educational activities. transplant recipients. Transplant Proc 2011;43:1159–61. 15. Bestard O, Lucia M, Crespo E, et al. Pretransplant immediately early- Patient consent for publication Not required. 1-specific T cell responses provide protection for CMV infection after Ethics approval In accordance with Royal Decree 1090/2015 of 4 December kidney transplantation. Am J Transplant 2013;13:1793–805. concerning the regulation of clinical trials with medicinal products in Spain, 16. Cantisán S, Lara R, Montejo M, et al. Pretransplant interferon-γ multicenter clinical trials only require the approval of a single Medicinal Research secretion by CMV-specific CD8+ T cells informs the risk of CMV replication after transplantation. Am J Transplant 2013;13:738–45. Ethics Committee (reference MREC) and of the Spanish Agency of Medicines and 17. Manuel O, Husain S, Kumar D, et al. Assessment of cytomegalovirus- Medical Devices (AEMPS). This clinical trial has been approved by the reference specific cell-mediated immunity for the prediction of cytomegalovirus MREC of the province of Cordoba and the AEMPS (Code: FCO-CYT-2018-01; disease in high-risk solid-organ transplant recipients: a multicenter EudraCT Number: 2018-003300-39). cohort study. Clin Infect Dis 2013;56:817–24. 18. Giulieri S, Manuel O. QuantiFERON®-CMV assay for the assessment Provenance and peer review Not commissioned; externally peer reviewed. of cytomegalovirus cell-mediated immunity. Expert Rev Mol Diagn Open access This is an open access article distributed in accordance with the 2011;11:17–25. Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which 19. Páez-Vega A, Poyato A, Rodriguez-Benot A, et al. Analysis of permits others to distribute, remix, adapt, build upon this work non-commercially, spontaneous resolution of cytomegalovirus replication after and license their derivative works on different terms, provided the original work is transplantation in CMV-seropositive patients with pretransplant CD8+IFNG+ response. Antiviral Res 2018;155:97–105. properly cited, appropriate credit is given, any changes made indicated, and the use 20. Westall GP, Cristiano Y, Levvey BJ, et al. A randomized is non-commercial. See: http://​creativecommons.​org/​licenses/​by-​nc/​4.​0/. study of Quantiferon-CMV directed versus fixed duration ValganciclovirProphylaxis to reduce late CMV following lung transplantation. Transplantation 2018;21. 21. Kumar D, Mian M, Singer L, et al. An interventional study using References cell-mediated immunity to personalize therapy for cytomegalovirus 1. Torre-Cisneros J, Aguado JM, Caston JJ, et al. Management of infection after transplantation. Am J Transplant 2017;17:2468–73. cytomegalovirus infection in solid organ transplant recipients: 22. Chow SC, Shao J, Wang H. Sample Size Calculation in Clinical SET/GESITRA-SEIMC/REIPI recommendations. Transplant Rev Research. In: Chow SC, Jones B, Liu JP, et al, eds. Large sample 2016;30:119–43. tests for proportions. eds, 2008: 83–111. 2. Kotton CN, Kumar D, Caliendo AM, et al. The transplantation 23. Santos CAQ, Brennan DC, Yusen RD, et al. Incidence, risk factors Society international CMV consensus group. The third International and outcomes of delayed-onset cytomegalovirus disease in a large consensus guidelines on the management of cytomegalovirus in retrospective cohort of lung transplant recipients. Transplantation solid-organ transplantation. Transplantation 2018;102:900–31. 2015;99:1658–66. 8 Paez-Vega A, et al. BMJ Open 2019;9:e030648. doi:10.1136/bmjopen-2019-030648