Prosecution Insights
Last updated: April 19, 2026
Application No. 18/549,158

Treatment of Breast Cancer with Amcenestrant and Palbociclib

Non-Final OA §103
Filed
Sep 05, 2023
Examiner
LEESER, ERICH A
Art Unit
1622
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Pfizer, Inc.
OA Round
1 (Non-Final)
82%
Grant Probability
Favorable
1-2
OA Rounds
2y 3m
To Grant
95%
With Interview

Examiner Intelligence

Grants 82% — above average
82%
Career Allow Rate
773 granted / 948 resolved
+21.5% vs TC avg
Moderate +14% lift
Without
With
+13.5%
Interview Lift
resolved cases with interview
Typical timeline
2y 3m
Avg Prosecution
15 currently pending
Career history
963
Total Applications
across all art units

Statute-Specific Performance

§101
1.4%
-38.6% vs TC avg
§103
12.7%
-27.3% vs TC avg
§102
22.0%
-18.0% vs TC avg
§112
38.4%
-1.6% vs TC avg
Black line = Tech Center average estimate • Based on career data from 948 resolved cases

Office Action

§103
DETAILED ACTION This action is in response to Applicant’s submission dated September 5, 2023, in which Applicant amended claims 3, 5, 7, 9-11, 14-15, 17-25, and 27, and canceled claims 4, 26, and 28-32. 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. 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 non-obviousness. Determining the scope and contents of the prior art. Claims 1-3, 5-25, and 27 are rejected under 35 U.S.C. § 103 as being unpatentable over WO 2019/020559. WO 2019/020559 discloses a method of treating breast cancer in a patient in need thereof (p. 4, ln. 19-21, “…Herein is also provided a method of treating the pathological conditions indicated above, particularly breast cancer, comprising co-administering to a subject in need thereof palbociclib and compound (1) or a pharmaceutically acceptable salt thereof…”; p. 22, table 1, “…Efficacy of compound (1) combined with palbociclib against subcutaneous MCF7-Y537S human breast cancer xenograft in nude mice…”), comprising orally administering to the patient amcenestrant, or a pharmaceutically acceptable salt thereof (p. 16, example 2, ln. 6-10, “…The treated groups included compound (1) at 5 mg/kg alone, palbociclib at 100 mg/kg alone, and the combination of compound (1) and palbociclib at the same dose and regime. Ascertaining the difference between the prior art and the claims at issue. Compound (1) was orally dosed twice a day (BID)…”; p. 22, table 1, row 4, “…Compound (1) + Palbociclib…”; it is understood that compound (1) is amcenestrant, see p. 1, ln. 13-14, “…6-(2,4-dichlorophenyl)-5-[4-[(3S)-1-(3-fluoropropyl)pyrrolidine-3-yl]oxyphenyl]-8,9-dihydro-7H-benzo[7]annulene-2-carboxylic acid…”) and orally administering to the patient palbociclib, or a pharmaceutically acceptable salt thereof, at a dose of 75-125 mg. once daily (pages 4, ln. 19-21, “…Herein is also provided a method of treating the pathological conditions indicated above, particularly breast cancer, comprising co-administering to a subject in need thereof palbociclib…”; p. 16, example 2, ln. 6-10, “…palbociclib at 100 mg/kg alone, and the combination of compound (1) and palbociclib at the same dose and regime … and palbociclib was orally dosed once a day (QD) for 30 days…”; p. 22, table 1, row 4, “…Compound (1) + Palbociclib…”), but does not disclose wherein the dose of amcenestrant is more specifically 200-400 mg once daily. It would have been obvious to a medicinal chemist of ordinary still in the relevant art; however, to optimize the dose of amcenestrant to be 200-400 mg once daily through routine experimentation. Resolving the level of skill in the art. The Court has addressed this obviousness issue: “The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 12 (2007). “When there is a design need or market pressure to solve a problem and there are finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, … the fact that a combination was obvious to try might show that it was obvious”. Id. at 17. That is exactly the case here. The specific dosage range of amcenestrant of 200-400 mg once daily is a very finite list and Applicant was not left to pick and choose from a generic disclosure. Considering objective evidence present in the application indicating obviousness or non-obviousness. In the absence of any substantiated unexpected property of the claimed dose of amcenestrant in the specific range of 200-400 mg once daily combined with palbociclib in the dosage range of 75-125 mg once daily, then non-obviousness cannot be acknowledged for the claimed subject matter. Conclusion Any inquiry concerning this communication or earlier communications from the Examiner should be directed to ERICH A LEESER whose telephone number is (571) 272-9932. The Examiner can normally be reached Monday through Friday from 10-6 PST, M-F. PST. If attempts to reach the Examiner by telephone are unsuccessful, the Examiner’s supervisor, Mr. James Alstrum-Acevedo can be reached at (571) 272-5548. The fax number for the organization where this application is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) toll-free at 866-217-9197. If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ERICH A LEESER/Primary Examiner, Art Unit 1622 United States Patent and Trademark Office Tel. No.: (571) 272-9932
Read full office action

Prosecution Timeline

Sep 05, 2023
Application Filed
Jan 24, 2026
Non-Final Rejection — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12590082
FUSED TRICYCLIC DERIVATIVE AND PHARMACEUTICAL APPLICATION THEREOF
2y 5m to grant Granted Mar 31, 2026
Patent 12589099
ALPHA-1062 FOR TREATING TRAUMATIC BRAIN INJURY
2y 5m to grant Granted Mar 31, 2026
Patent 12590106
SPIROMACROCYCLIC OREXIN 2 RECEPTOR AGONISTS
2y 5m to grant Granted Mar 31, 2026
Patent 12570622
THERAPEUTIC COMPOUNDS
2y 5m to grant Granted Mar 10, 2026
Patent 12565518
HYBRID CYCLIC LIBRARIES AND SCREENS THEREOF
2y 5m to grant Granted Mar 03, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
82%
Grant Probability
95%
With Interview (+13.5%)
2y 3m
Median Time to Grant
Low
PTA Risk
Based on 948 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month