DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 5-10, 12-17 and 23-25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Burrell in view of “Penetration of an antimicrobial zinc-sugar alcohol complex into Streptococcus mutans biofilms” by Lim et al. (Lim, copy provided by applicant in parent application 17/673,532 on 17 July 2022).
Regarding claim 1, Burrell teaches a method of preventing or ameliorating the accumulation of biofilm on a surface by treating the surface with a solution comprising an antimicrobial metals (including zinc, see paragraph 67) and a sugar alcohol such as erythritol or mannitol (paragraph 159), but does not teach the particular molar ratio claimed. Lim teaches that this specific ratio of zinc chloride to erythritol has particularly effective antimicrobial properties (see e.g. first paragraph of “Results”) against biofilms. Accordingly, it would have been obvious to use zinc and erythritol at the specified molar ratio as taught by Lim in order to enhance the antimicrobial effects of the surface treatment of Burrell.
Regarding claims 5 and 12, Lim teaches the claimed concentrations of zinc and erythritol (see third paragraph of “Penetration of zinc and erythritol in to biofilms”).
Regarding claims 6-8, and 10, Burrell teaches treating the surface of a urinary catheter (paragraph 129), which is a critical device (see applicant’s specification at paragraph 114).
Regarding claim 9, Burrell teaches a method of preventing infection by treating the surface of a catheter with a solution comprising an antimicrobial metals (including zinc, see paragraph 67) and a sugar alcohol such as erythritol or mannitol (paragraph 159), but does not teach the particular molar ratio claimed. Lim teaches that this specific ratio of zinc chloride to erythritol has particularly effective antimicrobial properties (see e.g. first paragraph of “Results”) against biofilms. Accordingly, it would have been obvious to use zinc and erythritol at the specified molar ratio as taught by Lim in order to enhance the antimicrobial effects of the surface treatment of Burrell.
Regarding claim 13, Burrell teaches an antimicrobial compound suitable for coating a medical device comprising an antimicrobial metals (including zinc, see paragraph 67) and a sugar alcohol such as erythritol or mannitol (paragraph 159), but does not teach the particular molar ratio claimed. Lim teaches that this specific ratio of zinc chloride to erythritol has particularly effective antimicrobial properties (see e.g. first paragraph of “Results”) against biofilms. Accordingly, it would have been obvious to use zinc and erythritol at the specified molar ratio as taught by Lim in order to enhance the antimicrobial effects of the surface treatment of Burrell.
Regarding claim 14, Burrell teaches that lubricious materials may be used (e.g. polyurethane foam, see paragraph 106, see also paragraph 162).
Regarding claim 15, Burrell teaches that more than one antimicrobial agent may be used (see e.g. paragraph 61: “a therapeutically effective amount of one or more antimicrobial metals”).
Regarding claim 16, Burrell teaches treating the surface of a urinary catheter, which is a critical device (see applicant’s specification at paragraph 114).
Regarding claims 17 and 23-25, Burrell teaches applying coating of claim 13 to a urinary catheter.
Claim(s) 13 and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over US Pre-Grant Publication 2011/0009831 to Burkholz et al. (Burkholz) in view of Lim.
Regarding claim 13, Burkholz teaches a catheter (10) used intravenously (paragraph 29), on which an antimicrobial coating is provided (70, see paragraph 32). Burkholz does not teach the use of zinc chloride and erythritol and is silent to any ratio therebetween. Lim teaches that this specific ratio of zinc chloride to erythritol has particularly effective antimicrobial properties (see e.g. first paragraph of “Results”) against biofilms. Accordingly, it would have been obvious to use zinc and erythritol at the specified molar ratio as taught by Lim in order to enhance the antimicrobial effects of the surface treatment of Burkholz.
Regarding claims 23 and 26, Burkholz teaches an intravenous catheter (paragraph 29).
Response to Arguments
Applicant's arguments filed 27 January 2026 have been fully considered but they are not persuasive.
With respect to the argument that Burrell does not teach the specific molar ratio, the examiner does not contest this. However, the limitation is taught by Lim as discussed above.
With respect to the argument that Lim is non-analogous art, the examiner is not persuaded. Lim is specifically directed toward combating microbial biofilms. Since the problem being addressed by the applicant in using zinc and erythritol in the specified ratio to combat biofilms, the teachings of Lim are, at a minimum, pertinent to the problem faced by the inventor.
With respect to the argument that Burrell does not identify zinc-related irritation or toxicity, this limitation is not present in the claims and therefore does not present any barrier to the prima facie case of obviousness discussed above.
With respect to the applicability of Lim to catheter and medical device environments, as noted above, Lim is directed to combating biofilms. One of ordinary skill in the art would have been motivated to research compounds known to be effective against biofilms, and in so doing would naturally be led to teachings such as or commensurate with those of Lim.
With respect to the declaration, the examiner does not agree that the efficacy of the claimed combination is properly considered to be unexpected. Lim specifically indicates synergistic and highly effective results when using zinc and erythritol in the specified ratio. The examiner therefore does not agree that results which are predicted by the prior art are unexpected. Further with respect to the irritation and toxicity elements of the declaration, the examiner notes that this discussion does not have a nexus with the claims and therefore cannot sustain a finding of secondary considerations of non-obviousness. Furthermore, there is no evidence of record suggesting that toxicity and irritation reaction is significantly different between oral and other medical uses. This also indicates that the declaration does not set forth a sufficient evidentiary basis to support a finding of secondary considerations of non-obviousness.
In view of the above, the examiner holds that the invention as currently claimed is obvious.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PHILIP E STIMPERT whose telephone number is (571)270-1890. The examiner can normally be reached Monday-Friday, 8a-4p.
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/PHILIP E STIMPERT/Primary Examiner, Art Unit 3783 3 April 2026