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Purvis, J.

Publications and source records attributed to Purvis, J..

2 recordsLinked to original sources

Commitments by the biopharmaceutical industry to clinical trials transparency: the evolving environment

BackgroundSponsors of clinical trials have ethical obligations to register protocols, to report study results and to comply with applicable legal requirements.\n\nObjectiveTo evaluate public commitments to trial disclosure and rates of disclosure by members and non-members of the European Federation of Pharmaceutical Industries and Associations (EFPIA) and/or the Pharmaceutical Research and Manufacturers of America (PhRMA).\n\nStudy selectionWebsites of the top 50 biopharmaceutical companies by 2015 sales were searched for statements relating to trial data disclosure. Disclosure of trial results completed by biopharmaceutical industry and non-industry sponsors of at least 30 trials (2006-2015) was assessed using TrialsTracker.\n\nFindingsAmong the top 50 companies, 30 were EFPIA/PhRMA members and 20 were non-members, of which 26 and none, respectively, had a statement on their website committing to the disclosure of trials data. Of 29 377 trials in TrialsTracker, 9511 were industry-sponsored (69 companies) and 19 866 were non-industry-sponsored (254 institutions). The overall mean disclosure rate was 55%, with higher rates for industry (74%) than for non-industry sponsors (46%). Of the 30 companies within the top 50 with data in TrialsTracker, the mean disclosure rate was 76% (77% for EFPIA/PhRMA members [n = 25] versus 67% for non-members [n = 5]).\n\nConclusionsMost of the top 50 biopharmaceutical companies have publicly committed to the disclosure of trial data. Industry sponsors have responded to the ethical and legal demands of trial disclosure to a greater extent than non-industry sponsors, and now disclose three quarters of their trials.

scientific communication and education

Rapid DNA Replication Origin Licensing Protects Stem Cell Pluripotency

Complete and robust human genome duplication requires loading MCM helicase complexes at many DNA replication origins, an essential process termed origin licensing. Licensing is restricted to G1 phase of the cell cycle, but G1 length varies widely among cell types. Using quantitative single cell analyses we found that pluripotent stem cells with naturally short G1 phases load MCM much faster than their isogenic differentiated counterparts with long G1 phases. During the earliest stages of differentiation towards all lineages, MCM loading slows concurrently with G1 lengthening, revealing developmental control of MCM loading. In contrast, ectopic Cyclin E overproduction uncouples short G1 from fast MCM loading. Rapid licensing in stem cells is caused by accumulation of the MCM loading protein, Cdt1. Prematurely slowing MCM loading in pluripotent cells not only lengthens G1 but also accelerates differentiation. Thus, rapid origin licensing is an intrinsic characteristic of stem cells that contributes to pluripotency maintenance.

cell biology