A Rapid and Sensitive Liquid Chromatography-Tandem Mass Spectrometry Bioanalytical Method for the Quantification of Encorafenib and Binimetinib as a First-Line Treatment for Advanced (Unresectable or Metastatic) Melanoma—Application to a Pharmacokinetic Study

Round 1

Reviewer 1 Report

Manuscript Number: Molecules-2063042

Manuscript title: A Rapid and Sensitive Liquid Chromatography-Tandem Mass Spectrometry Bioanalytical Method for the Quantification of Encorafenib (BRAF Inhibitor) and Binimetinib (MEK Inhibitor) as a First-Line Treatment for Advanced (Unresectable Or Meta-static) Melanoma. Application to a Pharmacokinetic Study

A) Major

1. There is little originality in this research – there is similar method and identical drugs in the paper [1]. The only differences in present manuscript compared to mentioned article [1] are:

·       different mass spec and hplc producer

·       a little different chromatographic conditions

·       different matrix

Because of only few differences between this two manuscripts in reviewer opinion presented work is more like optimization of method described in [1] rather than development of method. Nevertheless from technical point o view the experiments were well conducted and results were described properly. Additionally the Authors properly cited mentioned manuscript.

B) Minor – there are a few of inaccuracies in presented manuscript:

1. The title is too long – maybe the Authors should remove information in brackets.
2. In the abstract there is lack of PK study results. The Authors may add the result of PK study, instead of first few sentences which in reviewer opinion are unnecessary.  
3. There is lack of the meaning of the abbreviations in abstract section.
4. The introduction is focused in 70% in drugs description and only in 30% in aim of the conducted study. If the aim was to developed method and its used in PK study, there should be opposite proportions.
5. The meaning of the abbreviations in main manuscript are later than used of abbreviations.
6. In Result & Discussion section there is lack of meaning of the IS abbreviation.
7. Line 170 please add the meanings of quality control points abbreviations.
8. The matrix effect is more proper than matrix factor – line 188.
9. Figure 4 is unnecessary.
10. The Authors should shortly describe the PK protocol in M&M section – which model was used, what parameters were calculated.
11. In table 7 the Authors used t_1/2 abbreviation – it should be precise which half-life it is – probably t_1/2β = t_1/2kel which is half-life in elimination phase.
12. Line 261 – there is probably mistake of the name of equipment names and producer – in reviewer opinion Acquity UPLC is produced by WATERS (is the UPH the same as UPLC H-class system?) and the mass spec is Xevo TQD not the Acquity TQD.
13. There is a few extra space between words – lines: 25, 68, 160, 169, 172, 182, 184, 204, 233, 357.

References

[1] Attwa, M.W.; Darwish, H.H.; Al-Shakliah, N.S.; Kadi, A.A. A Validated LC–MS/MS Assay for the Simultaneous Quantification of the FDA-Approved Anticancer Mixture (Encorafenib and Binimetinib): Metabolic Stability Estimation. Molecules. 2021, 26, 2717.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

This is an interesting paper and is well designed and carried out. It is difficult to achieve the fast, high sensitivity and selectivity the authors did while using a small sample volume, in a complex matrix. There are some minor typographical errors like in L 277-8 where "H" should be "h" (for hour?) and L 303 should have "vortexed' rather than "vortexes'. The only improvement I can suggest is for a comparison of m/z ion ratios obtained for the sample and standard solutions as further confirmation of peak purity and identity. 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

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