Drugs and convalescent plasma therapy for COVID-19: a survey of the interventional clinical studies in Italy after 1 year of pandemic

Abstract

Background

The 2019 novel coronavirus disease (COVID-19) pandemic has highlighted the importance of health research and fostered clinical research as never before. A huge number of clinical trials for potential COVID-19 interventions have been launched worldwide. Therefore, the effort of monitoring and characterizing the ongoing research portfolio of COVID-19 clinical trials has become crucial in order to fill evidence gaps that can arise, define research priorities and methodological issues, and eventually, formulate valuable recommendations for investigators and sponsors. The main purpose of the present work was to analyze the landscape of COVID-19 clinical research in Italy, by mapping and describing the characteristics of planned clinical trials investigating the role of drugs and convalescent plasma for treatment or prevention of COVID-19 disease.

Methods

During an 11-month period between May 2020 and April 2021, we performed a survey of the Italian COVID-19 clinical trials on therapeutic and prophylactic drugs and convalescent plasma. Clinical trials registered in the Italian Medicines Agency (AIFA) and ClinicalTrials.gov websites were regularly monitored. In the present paper, we report an analysis of study design characteristics and other trial features at 6 April 2021.

Results

Ninety-four clinical trials planned to be carried out in Italy were identified. Almost all of them (91%) had a therapeutic purpose; as for the study design, the majority of them adopted a parallel group (74%) and randomized (76%) design. Few of them were blinded (33%). Eight multiarm studies were identified, and two of them were multinational platform trials. Many therapeutic strategies were investigated, mostly following a drug repositioning therapeutic approach.

Conclusions

Our study describes the characteristics of COVID-19 clinical trials planned to be carried out in Italy over about 1 year of pandemic emergency.

High level quality clinical trials were identified, although some weaknesses in study design and replications of experimental interventions were observed, particularly in the early phase of the pandemic.

Our findings provide a critical view of the clinical research strategies adopted for COVID-19 in Italy during the early phase of the pandemic. Further actions could include monitoring and follow-up of trial results and publications and focus on non-pharmacological research areas.

Introduction

The emerging SARS-CoV-2 coronavirus disease, known as COVID-19, has rapidly developed into a pandemic with a disruptive impact on health and economy. The clinical research community worldwide has responded to the pandemic at an unprecedented speed to produce evidence to prevent, diagnose, and treat COVID-19. A massive number of clinical trials have been registered at the various dedicated web registries, and as the number of clinical trials has increased, the initiatives to map the clinical research landscape and its evolution over time have increased too [1,2,3,4,5,6].

Several analyses of the characteristics of the registered COVID-19 clinical trials have already been conducted [7,8,9], showing redundancy and methodological issues [7], thus highlighting the need for a better coordination and collaboration of the research effort. Indeed, monitoring ongoing clinical research can be crucial for the management of COVID-19 emergency since it offers information that may improve research coordination across research entities, both within and among countries. This would avoid unnecessary duplication and fragmentation of the efforts [10] and offer the opportunity to share knowledge on methodology at the planning stage of the trial with substantial improvement of the quality of the evidence [11].

In Italy, the Italian Medicine Agency (AIFA) was entrusted with the task of managing the submission and authorization process of all clinical trials on drugs for the treatment and prevention of COVID-19. Specifically, according to the “Cura Italia” Decree Art. 17 [12], all clinical trial protocols on medicinal products for human use and medical devices for patients affected by COVID-19 had to be evaluated by the Technical Scientific Committee (CTS) of AIFA and by the Ethics Committee of the National Institute for Infectious Diseases (INMI) Lazzaro Spallanzani (single National Ethics Committee for COVID-19 clinical studies). In compliance with such measure, the list of authorized pharmacological COVID-19 clinical trials and related study protocols are made available in the AIFA website, whereas clinical trials of non-pharmacological interventions (such as infusion of plasma from convalescent COVID-19 patients) as well as pharmacological study proposals still under evaluation or rejected are not present in the website.

The aims of the measures introduced with the “Cura Italia” decree were to speed up the approval process, guarantee a highly qualified assessment, ensure the transparency of the approval process, and at the same time, facilitate the exchange of information within the scientific community [13].

In this context, the Working Group “Clinical Trials” of the Italian National Institute of Health [Istituto Superiore di Sanità (ISS)] has regularly mapped interventional trials on medicinal products and convalescent plasma planned in Italy, by integrating information from the AIFA website and the ClinicalTrials.gov website. Nine infographics were produced and published between 29 May 2020 and 22 April 2021. The main objective was to disseminate useful information to researchers, health professionals, funders, policy makers, and citizens. Here, we report the results of the mapping analysis of clinical research on COVID-19 in Italy updated to about 1 year after the start of the pandemic officially declared by WHO on 11 March 2020 [14].

Methods

Study types and data sources

We identified and analyzed the preventive and therapeutic COVID-19 interventional clinical studies with drugs and plasma from convalescent patients planned in Italy at about 1 year from the beginning of the pandemic emergency [14].

To perform this survey, we used two data sources. The main source was the open-access AIFA website specifically established for COVID-19 clinical studies [15] in compliance with the Decree Law “Cura Italia” providing extraordinary measures to face the medical emergency (published on 18 March 2020) [12]. The list of pharmacological COVID-19 clinical trials evaluated and fully approved by either the CTS of AIFA and the National Unique Ethic Committee of the INMI Lazzaro Spallanzani—regularly updated—is available on the AIFA website. The related study protocols are also accessible on the same website. The second data source was ClinicalTrials.gov website, the portal for globally conducted clinical trials of the National Institutes of Health—US National Library of Medicine [16], which made available the list of registered COVID-19 clinical trials with related study information.

Data collection and analysis

Data on COVID-19 clinical trials approved by AIFA were obtained through the periodic consultation of the dedicated website [15] and the download of the related study protocols. The following study information has been extracted: identification number (EudraCT Number), title, acronym, primary purpose (treatment, prevention), experimental intervention, phase, design (single group, parallel groups, cross-over, sequential), randomization (yes/no), masking (yes/no), multicentric study (yes/no), international study (yes/no), planned sample size, and sponsor type (Industry/No industry). All the collected information was included into an ad hoc established form. Data were updated to 6 April 2021.

The list of COVID-19 clinical trials registered on ClinicalTrials.gov portal [17] visited on 6 April 2021 was used. The list was obtained through the search term “COVID-19,” and the search synonyms “COVID,” “SARS-CoV-2,” “severe acute respiratory syndrome coronavirus 2,” “2019-nCoV,” “2019 novel coronavirus,” and “Wuhan coronavirus.” Clinical trials were extracted by applying the filter “Interventional (Clinical Trial)” in the field “Study Type.” The information data of selected studies were downloaded in “Comma-separated values” format by including “all available columns.”

By using the downloaded dataset, Italian studies have been identified by the presence of the “Italy” string in the “location” column. Whenever the location information was missing, Italian studies were identified by looking at data reported in “sponsor/collaborators” or “study title” or “principal investigator” columns. Clinical studies investigating “medical device,” “diagnostic test,” “behavioural interventions,” “procedure,” “radiation,” “dietary supplement,” and “other” were excluded. Study data (see list described above for studies in the AIFA website) were derived from the downloaded information. Studies were identified through their assigned NCT number.

Any ambiguity detected during the categorization of the available information, such as the classification of the characteristics of the study design or experimental intervention, was collegially discussed and a decision was taken by common consent.

A procedure was developed to integrate the two data sources: the list of Italian clinical trials identified using the ClinicalTrials.gov registry was compared with that presented in the AIFA website in order to detect any eventual duplicates. In case of duplicates, the information reported in the AIFA website was considered.

The pharmacological interventions were classified by using the DrugBank database linked to the browser The Anatomical Therapeutical Chemical Classification System (ATC), which allows to get detailed information on the drugs and their specific targets [18].

Descriptive analyses of the characteristics of the study designs (overall and through data stratification by source) have been done by calculating frequencies and relative frequencies for categorical/categorized variables, and medians with interquartile range for continuous variables. To this aim, the sample size was categorized as 1-100, 101-1000, >1000. Furthermore, the experimental interventions have been listed and summarized by therapeutic classes and subclasses.

Multiarm trials were listed and platform trials—which investigate multiple treatments simultaneously with the aim of finding the best treatment for a disease [19]—were extracted.

The statistical software STATA 16 was used.

Results

Collection of Italian clinical trials

Figure 1 shows the detailed procedure used for the identification of the interventional clinical studies planned in Italy. On the 6th of April 2021, 66 pharmacological COVID-19 clinical trials were present in the AIFA website. At the same date, 109 clinical trials enrolling patients in Italy were registered at ClinicalTrials.gov. Among them, 41 studies were excluded accordingly to the pre-defined selection criteria. The NCT04475120 (Escin) and NCT04322344 (Lactoferrin) studies were included under the food supplements category. The NCT04290871 and NCT04290858 (Nitric oxide) studies were included under the category “Others,” while considering the dosage and intravenous route of administration, the NCT04323514 (Vitamin C) study was considered as drug. Of the remaining 68 studies, 40 were excluded being duplicated in the AIFA list.

Fig. 1

Identification of COVID-19 interventional clinical studies. Flow diagram of identification of COVID-19 interventional clinical studies on drugs or convalescent plasma planned to be carried out in Italy (update: 6 April 2021). Data source: AIFA website [15]; ClinicalTrials.gov [17]. *Assumption on experimental interventions: Escin (study identification number: NCT04475120) and lactoferrin (study identification number: NCT04322344) were included under the category dietary supplements; Nitric oxide (study identification numbers: NCT04290871 and NCT04290858) was included under the category “other”; Vitamin C (study identification number: NCT04323514) was included under the category drug taking into account dosage and route of administration. ^§Clinical studies identified from ClinicalTrials.gov registry already identified from the AIFA website were considered duplicates and information reported on the AIFA website was considered for analyses

Finally, we conducted our analysis on 94 clinical trials of which 66 (70%) were registered at the AIFA website and 28 (30%) were retrieved from ClinicalTrials.gov.

Study characteristics

Table 1 shows the characteristics of the identified clinical trials both overall and separately for those listed in AIFA website and for those retrieved only on ClinicalTrials.gov registry. By considering all studies (n=94), 86 were therapeutic trials (91%) and 8 were preventive trials (9%). The majority of the studies were phase 2 (n=29, 34%), phase 2/3 (n=19, 22%), and phase 3 (n=32, 38%). The planned sample size was in the range of 101–1000 subjects in 53 (60%) trials, while 9 (10%) clinical studies envisaged the enrollment of more than 1000 patients (median sample size: 243 participants). Overall, 47,682 patients were planned to be recruited. With regard to the study design, 69 (74%) were parallel group trials, 70 (76%) were randomized, and 31 (33%) adopted masking procedures. The multicenter studies were 74 (80%) and 37 (40%) were multinational. Sponsor was pharmaceutical industry in 32 (34%) of the total studies.

Table 1 Study characteristics

Among studies retrieved only on ClinicaTrials.gov registry (28), we noted that 12 (46%) planned to enroll less than 100 patients, 11 (39%) had a single group design, 15 (56%) studies were randomized, 6 were masked (21%), 18 (64%) were multicenter, 6 (21%) were international studies, and 5 (18%) were industry sponsored.

Multiarm studies

Among 94 studies collected overall, 8 (9%) multiarm trials were identified (Table 2). All of these were multicentric trials and 6 out 8 (75%) had an Italian Sponsor. Two out of 8 (25%) multiarm trials were platform trials.

Table 2 Description of multiarm clinical trials

Experimental interventions and therapeutic classes

Table 3 shows the list of experimental interventions by considering all studies. Data source, identification number, title, and acronym have been listed for each trial investigating every experimental intervention. In detail, 63 different experimental interventions have been identified: 43 of them (68%) were investigated in single studies, 10 (16%) were present in 2 studies, and 10 (16%) were explored in at least 3 studies (Table 3). The most investigated treatment was convalescent plasma that was explored in 12 clinical trials, whereas 6 clinical trials planned to use hydroxychloroquine and other 6 were based on enoxaparin therapy. Noteworthy, among experimental interventions identified in Clinical Trials.gov registry not found in the AIFA database, in addition to the expected convalescent plasma and Vitamin C, some other drugs have been identified (Table 3).

Table 3 Experimental interventions: study details

Therapeutic classes and subclasses of experimental interventions are described in Table S1. The most frequent classes are immune-suppressors/immune-modulators (n=36), anti-thrombotic/anti-coagulants (n=22), plasma-derived (n=12), anti-viral (n=13), anti-malaria (n=7), and antibodies against SARS-CoV-2 (n=5). We have also identified 2 candidate vaccines: GRAd-COV2 with two trials (a phase I trial—EudractCT Number 2020-002835-31, and a phase II/III trial—EudractCT Number 2020-005915-39) and COVID-eVax with one trial (a phase I/II trial—EudractCT Number 2020-003734-20).

Notably, the identified clinical trials are focused on the use of molecules that belong to very different therapeutic classes (anti-osteoporotic, anti-diabetic, anti-gout, anti-hypertensive, anti-tumoral, hormones, statins), thus suggesting a drug repositioning approach.

Discussion

In response to the global coronavirus infection (COVID-19) emergency, a huge number of clinical trials exploring a variety of interventions have been proposed by the scientific community worldwide in order to search for efficacious therapeutic approaches. The main purpose of the present work was to analyze the landscape of COVID-19 clinical research in Italy, by mapping and describing the characteristics of planned clinical trials investigating the role of drugs and convalescent plasma for treatment or prevention of COVID-19 disease. In Italy, the AIFA was entrusted with the task of managing the submission and authorization process of all clinical trials on medicines for the treatment and prevention of COVID-19. Therefore, similarly to other National Competent Authorities in Europe, AIFA set up simplified, accelerated procedures (“Cura Italia” Decree, 18 March 2020 [12]). A list of all authorized studies, including full protocols, is regularly updated and publicly accessible in the AIFA, thereby providing the opportunity for mapping and tracking COVID-19 clinical trials. To our knowledge, not all Competent Authorities in Europe have provided open access to the same amount of information.

Unfortunately, information on pharmacological clinical trials that are still under evaluation or have been denied authorization is not made available on AIFA website. Moreover, studies on non-pharmacological interventions, even if submitted at the single National Ethics Committee, do not undergo AIFA evaluation. We therefore extended our search to the ClinicalTrials.gov registry, which is widely used by investigators and sponsors worldwide and reports also some information on the study protocols. Data from the two sources were properly integrated (see the “Methods” section) to avoid duplication.

At 6 April 2021, at about 1 year since the WHO declaration of COVID-19 pandemic, we identified a considerable number of clinical trials on drugs or plasma from convalescent patients planned to be carried out in Italy, thus being aligned with international activities [1,2,3,4,5,6].

Overall, our survey showed that some worthwhile clinical characteristics were widely implemented (parallel groups, randomization), whereas other were frequently missed (blinding), likely suggesting difficulties concerning organization and conduction (such as packaging and labeling experimental products or preparing placebo) [7]. The majority of clinical trials reported considerable sample sizes (>100). Moreover, most of the studies were multicenter, indicating collaboration efforts among clinical sites, even at the international level, and active participation of Italian investigators in multinational networks. In fact, over the time, a progressive shift from small single site studies to multicenter, national, and international collaborative clinical trials (including multiarm studies) was observed (data not shown). Indeed, the networking among clinical researchers proposing similar experimental interventions was strongly supported also by AIFA [20]. However, evaluating whether this evolution has impacted on the quality and efficiency in the conduct of the studies is beyond the scope of our work.

Of note, several clinical trials were retrieved only from ClinicalTrials.gov registry. They were mainly single group design, unblinded, non-randomized, and small sample size studies, suggesting possible methodological issues for some of them. Moreover, multicenter and international clinical trials were less represented. By looking at experimental intervention, about half of them were focused on convalescent plasma that in Italy is not classified as “drug” and is under the technical and scientific control of the National Blood Center. Although the study on ClinicalTrials.gov NCT04323514 reported Vitamin C treatment as dietary supplement, we include the study in the survey as considering of the high dosage and the route of administration (intravenous) which determine its intended use as a drug and not as a supplement. Some explanations for the others pharmacological clinical trials found in the ClinicalTrials.gov website and not in the AIFA list might be hypothesized: they may represent studies still under evaluation or just planned, or even studies that have been denied authorization but were not removed from the website.

We found that some experimental interventions were investigated contemporaneously in different studies. This might be useful to build up a body of evidence to evaluate the efficacy of a given intervention, but might also lead to a fragmentation of the research and sub-optimal use of resources. This should be avoided in a pandemic scenario where the identification of potential treatments is an unmet need requiring “quick” responses by means of coordinated efforts and rigorously conducted clinical studies [7]. The use of “convalescent plasma” to prevent COVID-19 disease progression [21] may be taken as an example. In Italy, to provide a rapid and scientifically founded answer on the role of this approach, a national, randomized multicenter trial was carried out under the sponsorship of ISS and AIFA (TSUNAMI study, NCT04716556). This allowed the enrolment of 487 hospitalized patients with COVID-19 pneumonia from 27 clinical sites in Italy in less than 5 months (15 July to 8 December 2020) [22].

The characteristics of therapeutic interventions deserve some considerations. At the beginning of the COVID-19 outbreak, in Italy as everywhere in the world, most clinical trials were based on repositioning of drugs already approved for other indications and prescribed through a systematic off-label use. Consistently, most studies were classified as phase 2, phase 2/3, or phase 3. The most frequently reported therapeutic classes included antimalarial agents (prescribed on the basis of previous experience in SARS-COV 1 and MERS-COV diseases), immunosuppressant and immune-modulating drugs, anticoagulants, immunoglobulin, and antivirals used for other infections, such as lopinavir/ritonavir and favipiravir.

Regarding the experimental intervention, a shift in the distribution of therapeutic classes was observed over time [23], due to the lack of efficacy of some repurposed drugs (such as chloroquine) and the scientific knowledge acquired during the pandemic.

In the absence of an effective therapy, several studies were based on dietary supplements. The distinction between dietary supplement and drug is often faded, since the classification of a product in one of the two categories depends on various factors such as the type of substance, the dosage and the route of administration and, above all, the purpose of use [24]. Regulatory aspects reflect this ambiguity and thus it is not surprising that some Italian clinical trials, detected in ClinicalTrials.gov and for which the sponsor indicates the active intervention as “dietary supplement,” have never been submitted to the AIFA evaluation.

As expected, clinical trials submitted to AIFA included also preventive interventions with 2 candidate COVID-19 vaccines. A phase I study with the GRAd-COV2 vaccine was approved on 29 July 2020 and reached phase 2/3 on 19 February 2021. An additional phase I/II study was authorized on 03 February 2021 for COVID-EVAX vaccine.

A final analysis regards the trial sponsorship, with non-industrial sponsors, such as academic or public hospitals, supporting majority of the studies. This heavy involvement of nonprofit institutions indicates the willingness of investigators to promptly face the emergency taking advantage of previous experiences (even if limited) and of the available knowledge.

Our work has some limitations. We used ClinicaTrials.gov as source of data to integrate the information found in the AIFA website. However, there are some issues with this registry which need to be considered because the information reported in ClinicaTrials.gov—differently from study protocols submitted to regulatory authority—may be partial, not undergoing assessment for authorization, and not always updated [25]. A further limit is that we were unable to capture potential changes in the studies due to protocol amendments. However, due to the limited time of observation, we may reasonably hypothesize that such changes occurred in a small number of trials with a minor impact on their major features. In addition, we do not know the total number of proposals submitted to AIFA, the number of rejections, and the number of studies on hold waiting for resolution of queries.

Our mapping of Italian clinical trials allowed to analyze the early response of the clinical research community to the national and worldwide COVID-19 emergency. The deep investigation highlighted a wide clinical research landscape. The analyses of study design characteristics have showed that high level quality clinical trials were planned although some weaknesses have been observed in line with international activities. Therefore, our study suggests that coordination and collaboration, as well as expert clinical methodologists, are needed in health emergency.

Conclusions

To our knowledge, this is the first mapping of therapeutic clinical trials for COVID-19 disease performed in Italy since the beginning of the pandemic. This work was made possible due to the availability of study documents in the AIFA website which represents an important source of detailed information for sponsors, clinical researchers, and health care professionals and a stimulus to improve both clinical methodologies and planning of future research objectives.

In perspective, the following aspects can be analyzed: (i) description of the study endpoints and the populations included in the protocols, (ii) relationship between the methodological characteristics and the sponsorship, and (iii) monitoring of the trial completion and publication of results. This last point would be crucial in order to evaluate the fulfillment of the identified trials and, most importantly, the quality and efficacy of the clinical research strategy.