Publication rates and reported results in a cohort of gene- and cell-based therapy trials

Time to publication for results of clinical trials

BACKGROUND

Researchers conducting trials have a responsibility to publish the results of their work in a peer-reviewed journal, and failure to do so may introduce bias that affects the accuracy of available evidence. Moreover, failure to publish results constitutes research waste.

OBJECTIVES

To systematically review research reports that followed clinical trials from their inception and their investigated publication rates and time to publication. We also aimed to assess whether certain factors influenced publication and time to publication.

SEARCH METHODS

We identified studies by searching MEDLINE, Embase, Epistemonikos, the Cochrane Methodology Register (CMR) and the database of the US Agency for Healthcare Research and Quality (AHRQ), from inception to 23 August 2023. We also checked reference lists of relevant studies and contacted experts in the field for any additional studies.

SELECTION CRITERIA

Studies were eligible if they tracked the publication of a cohort of clinical trials and contained analyses of any aspect of the publication rate or time to publication of these trials.

DATA COLLECTION AND ANALYSIS

Two review authors performed data extraction independently. We extracted data on the prevalence of publication and the time from the trial start date or completion date to publication. We also extracted data from the clinical trials included in the research reports, including country of the study's first author, area of health care, means by which the publication status of these trials were sought and the risk of bias in the trials.

MAIN RESULTS

A total of 204 research reports tracking 165,135 trials met the inclusion criteria. Just over half (53%) of these trials were published in full. The median time to publication was approximately 4.8 years from the enrolment of the first trial participant and 2.1 years from the trial completion date. Trials with positive results (i.e. statistically significant results favouring the experimental arm) were more likely to be published than those with negative or null results (OR 2.69, 95% CI 2.02 to 3.60; 19 studies), and they were published in a shorter time (adjusted HR 1.92, 95% CI 1.51 to 2.45; 4 studies). On average, trials with positive results took 2 years to publish, whereas trials with negative or null results took 2.6 years. Large trials were more likely to be published than smaller ones (adjusted OR 1.92, 95% CI 1.33 to 2.77; 11 studies), and they were published in a shorter time (adjusted HR 1.41, 95% CI 1.18 to 1.68; 7 studies). Multicentre trials were more likely to be published than single-centre trials (adjusted OR 1.20, 95% CI 1.03 to 1.40; 2 studies). We found no difference between multicentre and single-centre trials in time to publication. Trials funded by non-industry sources (e.g.governments or universities) were more likely to be published than trials funded by industry (e.g. pharmaceutical companies or for-profit organisations) (adjusted OR 2.13, 95% CI 1.82 to 2.49; 14 studies); they were also published in a shorter time (adjusted HR 1.46, 95% CI 1.15 to 1.86; 7 studies).

AUTHORS' CONCLUSIONS

Our updated review shows that trial publication is poor, with only half of all trials that are conducted being published. Factors that may make publication more likely and lead to faster publication are positive results, large sample size and being funded by non-industry sources. Differences in publication rates result in publication bias and time-lag bias that may influence findings and therefore ultimately affect treatment decisions. Systematic review authors should consider the possibility of time-lag bias when conducting a systematic review, especially when updating their review.

FUNDING

This Cochrane review had no dedicated funding.

REGISTRATION

This review combines and updates two earlier Cochrane reviews. The two protocols and previous versions of the two updated reviews are available via 10.1002/14651858.MR000006 and 10.1002/14651858.MR000006.pub3 and 10.1002/14651858.MR000011 and 10.1002/14651858.MR000011.pub2.

Is Hospital Exemption an Alternative or a Bridge to European Medicines Agency for Developing Academic Chimeric Antigen Receptor T-Cell in Europe? Our Experience with ARI-0001

The hospital exemption (HE) allows for the use of advanced therapy medicinal products (ATMPs) next to marketing authorization (MA), but under special conditions. The HE is only applicable to individual patients treated in the hospital setting and it is limited to member states of the European Union (EU); HE is mainly conceded to the academic centers that developed the ATMP, being granted by the national competent authority (NCA), which, in the case of Spain, is the Spanish Agency of Medicines and Medical Devices (AEMPS). The HE follows strict standards of traceability, pharmacovigilance, and quality. In February 2021, our ATMP ARI-0001, a new autologous chimeric antigen receptor (CAR) targeting CD19, was approved by AEMPS under HE for patients >25 years with relapsed or refractory CD19⁺ acute lymphoblastic leukemia. This authorization was a first step in the development of, and access to, academic CAR T cell products in the EU. The fact that HE is limited to a specific country and hospital, the need of continuous evaluation by the NCA, and the potential future overlap with other centrally approved ATMPs, suggest that the HE could be used as an intermediate step before obtaining a centralized MA by the European Medicines Agency.