Address for correspondence: Jan Styczyński, Department of Pediatric Hematology and Oncology, Nicolaus Copernicus University in Toruń, Skłodowskiej-Curie 9, 85–094 Bydgoszcz, Poland, phone +48 52 58 54 860, fax +48 52 58 54 087, e-mail: jstyczynski@cm.umk.pl
Cytomegalovirus (CMV) infection is a major complication after allogeneic hematopoietic cell transplantation (allo-HCT), and a serious trigger for other sequelae [1–3]. The introduction of letermovir into the prophylaxis of CMV infection has led to a large reduction of the CMV reactivation rate in seropositive adult patients after allo-HCT [4–5]. This effect obviously means fewer direct and indirect complications caused by the virus [6–8]. Successful prophylaxis alleviates the negative impact of recipient CMV-seropositivity and eventually results in lower non-relapse mortality and better overall survival [4, 5, 9].
Progress is still being maintained. Recent trials have shown the safety and efficacy of letermovir use for prolonged (200 days) prophylaxis, and also in other patient populations such as children, as well as in secondary prophylaxis [10].
Yet another new anti-CMV drug, maribavir, is in the pipeline. This antiviral has been shown to have efficacy in preemptive treatment and in resistant CMV infections [1]. Fortunately, both letermovir and maribavir have very beneficial safety profiles, unlike the old-generation anti-CMV antivirals. Interestingly, during the most recent Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT), half of the highest-scoring abstracts on infectious complications were dedicated to the topic of CMV, confirming that this is one of the most pressing issues in the current management of allo-HCT.
The coronavirus disease 2019 (COVID-19) pandemic is over, as announced by the World Health Organization (WHO) on 5 May. CMV infection after allo-HCT is not over, but, with new antivirals, it can be vastly reduced. The next step must be to find an effective vaccine against CMV. With the new mRNA technologies used for the anti-SARS-CoV-2 vaccine, hopes are high that transplant patients will finally be able to overcome the problem of CMV.
Authors’ contributions
JS — sole author.
Conflict of interest
The author declares no conflict of interest.
Financial support
None.
Ethics
The work described in this article has been carried out in accordance with The Code of Ethics of the World Medical Association (Declaration of Helsinki) for experiments involving humans; EU Directive 2010/63/EU for animal experiments; Uniform requirements for manuscripts submitted to biomedical journals.