Predictive factors of clinical outcomes in patients with COVID-19 treated with tocilizumab: A monocentric retrospective analysis

Giulia Cassone; Giovanni Dolci; Giulia Besutti; Luca Braglia; Paolo Pavone; Romina Corsini; Fabio Sampaolesi; Valentina Iotti; Elisabetta Teopompi; Marco Massari; Matteo Fontana; Giulia Ghidoni; Anaflorina Matei; Stefania Croci; Emanuele Alberto Negri; Massimo Costantini; Nicola Facciolongo; Carlo Salvarani

doi:10.1371/journal.pone.0262908

Peer Review History

Original SubmissionApril 11, 2021
8 Jun 2021 Decision Letter - Tai-Heng Chen, Editor PONE-D-21-11985 Clinical outcomes predictive factors in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis. PLOS ONE Dear Dr. Dolci, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Jul 23 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: No Reviewer #3: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes Reviewer #3: Yes ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: Dr Dolci, and colleagues addressed a nice study, “Clinical outcomes predictive factors in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis”. However, there are many concerns that must be address. Materials, methods, and Results Major concerns: 1. The glucocorticoids (GCs) along with or after TCZ should be included in the uni and multi models at table 1 and 2 analysis, once 42 and 50% of each group were on GCs therapy 2. The median follow-up of 12 days (range 8-19 days) is too short to evaluate the outcomes, the authors should extent at least until 28 days. 3. The authors decided to include TCZ in subcutaneous formulation, please provide different analysis for each one, once the PK/PD could be different, and based on result of this analysis, please add in discussion section an explanation supporting or not its use. Minor concerns: 1. The authors should include all abbreviation with meanings at the first time “CT scans performed at ER (???)” line 145, page 6 Reviewer #2: This is a single center retrospective review evaluating outcomes and predictor factors for the use of tocilizumab and COVID-19 infections. The study had a fairly large population of n=144. As this is a retrospective review, the conclusions and causality are difficult to infer. It is an interesting study as it proceeded the use of remdesivir. I did have some comments/suggestions for the authors: Other comorbidities associated with severe COVID were not included: pulmonary disease, stroke, kidney disease, and liver disease. What was the outcome of the non-responders who did not die? Were any of the individuals immunosuppressed at baseline? What was the cause of death for non-responders? Any further delineation on how sick patients were on admission (i.e. SOFA score) would be useful to understand the patient population in the study. Any report of co-infections or opportunistic infections in the non-responders? I would like further delineation on the use of SQ versus IV tocilizumab. Was there any difference in these groups and outcomes and deaths? Additionally, including the median time of initiation of symptoms and/or the median time of admission to administration tocilizumab therapy would be helpful in the responder versus non responder groups. I was also confused there is a variable in Table 3 of NIV or mechanical ventilation at time of tocilizumab therapy but I thought non-responders were identified as requiring mechanical ventilation or death. Table 1: Would consider using decimal points instead of commas for p-value column. Consider adding a column for responders as this should be the direct comparison to non-responders. It is less useful to compare non-responder to total population. Reviewer #3: Although the paper does highlight the paucity of information available on the utility of tocilizumab, unfortunately there are several flaws to the study. 1. The wording of the title is confusing. It would be preferable to read “Predictive factors of clinical outcomes in patients with COVID-19 …” rather than Clinical outcomes predictive factors in patients with COVID-19… 2. Multiple times throughout the paper, the writers use the term “heavy” – line 37, 64, 288 etc. It is unclear what is meant by this term and I suspect it may be a mistranslation. 3. I am concerned about the difference in administration of the tocilizumab – some patients received the drug subcutaneously and some intravenously. I believe a subanalysis demonstrating no difference between the two formulations would be prudent given that how the drug is administered may impact outcomes. Additionally, there does not seem to be any subanalysis to determine if there are differences that could be attributed to patients who received other treatments, including hydroxychloroquine, lopinavir/ritonavir or darunavir/cobicistat 4. Line 145 has “???”. I suspect something else was meant to be written here. 5. The six-category ordinal scale used as an outcome measure was not described 6. Overall, this is a small study that does not include appropriately defined outcome measures nor does it explore potential biases appropriately. The conclusions are not substantially different from the larger trials that the authors themselves cite, including REMAP-CAP and RECOVERY. ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No Reviewer #3: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0262908.r001
Revision 1
31 Oct 2021 Author Response MANUSCRIPT ID: PONE-D-21-11985R1 23rd July 2021 Dear Editor, We are very grateful for your constructive comments and suggestions to our paper entitled “Clinical outcomes predictive factors in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis.”. We here provide a point-by-point reply to the comments and we have incorporated the related changes in the manuscript. The page and lines reported refer to the manuscript with changes track. We thank for the thoughtful insights which helped to significantly improve the manuscript. Reviewer #1: Dr Dolci, and colleagues addressed a nice study, “Clinical outcomes predictive factors in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis”. However, there are many concerns that must be address. Materials, methods, and Results Major concerns: 1. The glucocorticoids (GCs) along with or after TCZ should be included in the uni and multi models at table 1 and 2 analysis, once 42 and 50% of each group were on GCs therapy. Authors’ reply: we are grateful for this comment. We have performed this analysis and added it to table 1. No associations with the outcomes were found. 2. The median follow-up of 12 days (range 8-19 days) is too short to evaluate the outcomes, the authors should extent at least until 28 days. Authors’ reply: we are grateful for this comment and we extended the follow-up to the last data available for each patient in our electronic system. The new median follow-up is 318 (IQR 51-428.5), but no variation in the primary outcome was witnessed. We updated the data in the manuscript (table 1 and page 18, line 203). 3. The authors decided to include TCZ in subcutaneous formulation, please provide different analysis for each one, once the PK/PD could be different, and based on result of this analysis, please add in discussion section an explanation supporting or not its use. Authors’ reply: we are grateful for these comments and we explored this approach previously but we did not include it in the paper as splitting the analysis by type of administration would be detrimental for sample size/power of each analysis. However, we formally added administration type in the variable selection procedure (last line of table 2) and no differences in response/death-intubation were associated to it. We also added this sentence at lines 249-250: “No significant difference in response rates was observed between patients treated with intravenous or subcutaneous tocilizumab.” Minor concerns: 1. The authors should include all abbreviation with meanings at the first time “CT scans performed at ER (???)” line 145, page 6. Authors’ reply: we modified the paper accordingly. Reviewer #2: This is a single center retrospective review evaluating outcomes and predictor factors for the use of tocilizumab and COVID-19 infections. The study had a fairly large population of n=144. As this is a retrospective review, the conclusions and causality are difficult to infer. It is an interesting study as it proceeded the use of remdesivir. I did have some comments/suggestions for the authors: Other comorbidities associated with severe COVID were not included: pulmonary disease, stroke, kidney disease, and liver disease. Authors’ reply: regarding pulmonary diseases COPD was included in the first version of the manuscript (Table 1). Regarding the other conditions, we added “Three patients had history of stroke or transient ischemic attack. Five patients had chronic kidney disease and one was a kidney transplant recipient. One patient had cirrhosis.” (page 10, line 203-205). What was the outcome of the non-responders who did not die? Authors’ reply: non-responders who did not die underwent a subsequent clinical improvement. To clarify the responder/non responder definition we added this sentence “Patients who initially declined and afterward improved on the six-category ordinal scale were defined as non-responders.” at pag. 7, line 161-162. Were any of the individuals immunosuppressed at baseline? Authors’ reply: at page 18, line 205-207, we added “Only two patients were on immunosuppressive therapy at baseline, one for ulcerative rectum-colitis and one for polymyalgia rheumatica. One patient had HIV infection.” What was the cause of death for non-responders? Authors’ reply: the cause of death for non responders was respiratory failure or intensive care-related complications. Any further delineation on how sick patients were on admission (i.e. SOFA score) would be useful to understand the patient population in the study. Authors’ reply: we added the sentence “Median Charlson’s score was 2 (range 0-8, IQR 2-3).” at pag. 7-8, lines 182-183. Any report of co-infections or opportunistic infections in the non-responders? Authors’ reply: we added this sentence in the results section, page 23, lines 266-267: “Regarding safety analysis one patient had an Acinetobacter baumanii sepsis and another one had oesophageal candidiasis, both in non-responders. No other opportunistic infection was detected.”. We have discussed this result at page 24, lines 300-302 as follow: “Notably, tocilizumab therapy showed a good safety profile. Nevertheless, it must be noticed that during the first months of the COVID-19 the awareness regarding secondary opportunistic infection was low and no specific screening for pulmonary aspergillosis was in place.” I would like further delineation on the use of SQ versus IV tocilizumab. Was there any difference in these groups and outcomes and deaths? Authors’ reply: we are grateful for this comment. As previously answered to Reviewer #1 we explored this approach previously but we did not include it in the paper as splitting the analysis by type of administration would be detrimental for sample size/power of each analysis. However, we formally added administration type in the variable selection procedure (last line of table 2) and no differences in response/death-intubation were associated to it. We also added this sentence at page 22 lines 249-250: “No significant difference in response rates was observed between patients treated with intravenous or subcutaneous tocilizumab.” Additionally, including the median time of initiation of symptoms and/or the median time of admission to administration tocilizumab therapy would be helpful in the responder versus non responder groups. Authors’ reply: we performed the suggested analysis, a slightly lower time from symptom onset to admission/first treatment was recorded for death/int patients (6 days in median) compared to the others (7, p = 0.038), likely due to more severe symptoms and quickier admission/treatment. No difference was found. We included the analysis in table one. I was also confused there is a variable in Table 3 of NIV or mechanical ventilation at time of tocilizumab therapy but I thought non-responders were identified as requiring mechanical ventilation or death. Authors’ reply: non responders were defined as “non-response to treatment was defined as at least one-point worsening of the clinical status after TCZ therapy.” (page 7, lines 161-162). Table 1: Would consider using decimal points instead of commas for p-value column. Consider adding a column for responders as this should be the direct comparison to non-responders. It is less useful to compare non-responder to total population. Authors’ reply: thank you for this comment, we modified table 1 accordingly. Reviewer #3: Although the paper does highlight the paucity of information available on the utility of tocilizumab, unfortunately there are several flaws to the study. 1. The wording of the title is confusing. It would be preferable to read “Predictive factors of clinical outcomes in patients with COVID-19 …” rather than Clinical outcomes predictive factors in patients with COVID-19… Authors’ reply: we are grateful for this suggestion, we modified the title accordingly: “Predictive factors of clinical outcomes in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis.”. 2. Multiple times throughout the paper, the writers use the term “heavy” – line 37, 64, 288 etc. It is unclear what is meant by this term and I suspect it may be a mistranslation. Authors’ reply: we are grateful for this suggestion, we modified the paper accordingly. 3. I am concerned about the difference in administration of the tocilizumab – some patients received the drug subcutaneously and some intravenously. I believe a subanalysis demonstrating no difference between the two formulations would be prudent given that how the drug is administered may impact outcomes. Additionally, there does not seem to be any subanalysis to determine if there are differences that could be attributed to patients who received other treatments, including hydroxychloroquine, lopinavir/ritonavir or darunavir/cobicistat Braglia, poi Giovanni Authors’ reply: we are grateful for this comment. We have performed an analysis considering different ways of tocilizumab administration and added it to table 1. No associations with the outcomes were found. 4. Line 145 has “???”. I suspect something else was meant to be written here. Authors’ reply: we are grateful for this comment and we apologize for the typo. We have changed the paper accordingly. 5. The six-category ordinal scale used as an outcome measure was not described. Authors’ reply: the six-category ordinal scale used was described in the original manuscript and you can find it at pages 6-7, lines 154-157 of the revised version. 6. Overall, this is a small study that does not include appropriately defined outcome measures nor does it explore potential biases appropriately. The conclusions are not substantially different from the larger trials that the authors themselves cite, including REMAP-CAP and RECOVERY. Authors’ reply: whereas we do agree that the conclusions are not substantially different from larger trials, we think that outcome measures were appropriately defined and potential biases explored in the context of the limitations that we have reported in the discussion. Furthermore, even though larger multicenter cohort studies and trials have been published, we describe one of the largest monocentric cohort of patients with COVID-19 treated with tocilizumab. We would like to express our great appreciation to you and the reviewers for the comments on our paper. If you have any further queries, please do not hesitate to contact us. Kind regards, Giovanni Dolci Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0262908.r002
10 Jan 2022 Decision Letter - Tai-Heng Chen, Editor Predictive factors of clinical outcomes in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis. PONE-D-21-11985R1 Dear Dr. Dolci, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Tai-Heng Chen, M.D. Academic Editor PLOS ONE Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The authors addressed all answers to the comments . I don’t need of further information and the manuscript is fine in the current format. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No https://doi.org/10.1371/journal.pone.0262908.r003
Formally Accepted
17 Jan 2022 Acceptance Letter - Tai-Heng Chen, Editor PONE-D-21-11985R1 Predictive factors of clinical outcomes in patients with COVID-19 treated with tocilizumab: a monocentric retrospective analysis. Dear Dr. Dolci: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Tai-Heng Chen Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0262908.r004

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