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 .
DETAILED ACTION
This Office action is responsive to Applicant's Remarks and Amendment after Non-Final Rejection, filed July 15, 2026. As filed, claims 1-11 are pending.
Response to Remarks
Applicant’s amendments have been fully considered and are entered. The status for each rejection and/or objection in the previous Office Action is set out below.
The rejection of claims 1-11 under 35 U.S.C. § 103 over Wu et al Yaoxue Tongbao (1980), 15(12), 37 (cited by Applicants in IDS) and further in view of Sykora et al. J Sep Sci 2019;42:89–129 is maintained. Applicants’ arguments filed 7/15/2026 have been fully considered but they are not persuasive.
Applicant's argue that the prior art does not specifically teach or suggest separation of the geometric isomers (Remarks page 4).
In response it is noted that per MPEP 716.02 guidance:” Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected.
In the instant case, the prior art by ‘Wu specifically teaches chromatographic separation of compound which corresponds to same compound of same purity as required by instant claims, by removing undesired impurities to give a high purity isomer compound which corresponds to claimed formula (1) in which P1, P2 are each hydrogen, A is a 2-hexenylene group and R2 is OH.
Consequently, the evidence of record shows that methods of chromatographic
separation of a starting mixture comprising a compound of formula (1) as claimed conducted on silica treated separation media were known in the art. Therefore, one of ordinary skill in the art following the teaching of the prior art and implementing the chromatographic separation method would had reasonable expectation of success to arrive at the claimed invention and separate from a mixture the isomer compound as claimed.
The Applicant has not shown evidence of substantially improved and unexpected results or properties between the instantly claimed separation of the compound of formula I by chromatography and the process for separation of the same compound disclosed by the prior art. Absent clear, convincing, side-by-side data demonstrating unobviousness vis-a-vis the prior art commensurate with the scope of protection sought and showing that the claimed process and process disclosed by prior art are distinct, the claims are considered prima facie obvious.
This rejection is still deemed proper and is therefore maintained.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 of this title, 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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-11 are rejected under 35 U.S.C. 103 as being unpatentable over Wu et al Yaoxue Tongbao (1980), 15(12), 37 (cited by Applicants in IDS) and further in view of Sykora et al. J Sep Sci 2019;42:89–129 (cited in PTO-892 attached herewith).
The prior art by Wu discloses purification of product PGE2 Prosta-5,13-dien-1-oic acid, 11,15-dihydroxy-9-oxo-, (5Z:, 13E, 15S) - RN 363-24-6 Z isomer of structure shown below, by a column containing AgNO3-treated silica gel stationary phase by using EtOAc-HOAc-petroleum ether-H2O (200:22.5:125:5) and EtOAc-HOAc-isooctane-H2O (200:22.5:140:5) as solvent systems.
The compound of the prior art corresponds to claimed formula (1) in which P1, P2 are each hydrogen ( instant claims 1, 4, 7, 8), A is a 2-hexenylene group
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(instant claim 2), R1 is
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(instant claim 3, 6) and R2 is hydroxy group.
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The differences between the teaching of the prior art and the claims at issue is that the prior art teaches AgNO3-treated silica gel stationary phase for separation of the product while instant claims require acid modified silica with a carboxy group.
However, using acid modified silica gel for separation of isomers is known in the prior art.
The review article by Sykora teaches chromatographic stationary phases including sulfo or carboxy modified silica for separation of mixtures including isomer separation and discusses that such stationary phase possessing distinct selectivity than currently available commercial columns (abstract; Table 1 on page 91-96; instant claims 5, 9-11).
It would have been obvious to one of ordinary skill in the art at the time of the invention to separate the isomers of prostaglandins by modified silica as stationary phases as discussed by Wu and to utilize acid modified silica as stationary phase as taught by Sykora, because the prior art teaches that alternative modified silica gel stationary exhibit enhanced selectivity in the separation of isomers.
In conclusion, the prior art as a whole as taught by Wu and Sykora teach the elements of the claimed method for separating isomers of prostaglandins, that the invention would be prima facie obvious to one of ordinary skill. Therefore, before the effective filing date of the claimed invention based on the teachings of the cited prior art, one of ordinary skill in the art would have an expectation of success in arriving at the claimed invention.
"Exemplary rationales that may support a conclusion of obviousness include: (A) Combining prior art elements according to known methods to yield predictable results ". See MPEP § 2143 .
Consequently, absent a showing of unexpected results, the instant claims are obvious over the prior art.
Conclusion
Claims 1-11 are rejected.
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 extension fee 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 date of this final action.
Telephone Inquiry
Any inquiry concerning this communication or earlier communications from the
examiner should be directed to:
Ana Muresan
(571) 270-7587
Ana.Muresan@uspto.gov
The examiner can normally be reached Monday - Friday (9:00AM - 5:30PM).
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Scarlett Goon can be reached at 571-270-5241. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ANA Z MURESAN/Primary Examiner, Art Unit 1692
