Ekaterina S. Pak, Ph.D.

Ekaterina S. Pak, Ph.D.

Dr. Pak’s practice focuses on preparation and prosecution of U.S. and international patent applications, as well as freedom-to-operate, patentability, and due diligence assessments. Kat has experience in a wide range of technical areas in the life sciences space, including engineered proteins, gene editing, cell therapy, environmental testing, diagnostics, and disease treatment methods.


Professional Experience

Registered Patent Agent, Casimir Jones S.C., March 2023 to present

Registered Patent Agent, Honigman LLP, August 2019-February 2023

Staff Scientist, Choate Hall & Stewart LLP, June 2016 – April 2019



Harvard University, Ph.D., Biological and Biomedical Sciences, 2016

Massachusetts Institute of Technology, B.S., Biological Engineering, 2009



United States Patent and Trademark Office



Pak E, Segal RA. Hedgehog Signal Transduction: Key Players, Oncogenic Drivers, and Cancer Therapy. Dev Cell. 2016 Aug 22;38(4):333-44.


Pak E, Segal RA, Stiles CD. New progenitors NESTIN(g) in the EGL. Nat Neurosci. 2013 Dec;16(12):1710-2.


Filbin MG, Dabral SK, Pazyra-Murphy MF, Ramkissoon S, Kung AL, Pak E, Chung J, Theisen MA, Sun Y, Franchetti Y, Sun Y, Shulman DS, Redjal N, Tabak B, Beroukhim R, Wang Q, Zhao J, Dorsch M, Buonamici S, Ligon KL, Kelleher JF, Segal RA. Coordinate activation of Shh and PI3K signaling in PTEN-deficient glioblastoma: new therapeutic opportunities. Nat Med. 2013 Nov;19(11):1518-23.


Zhao X, Ponomaryov T, Ornell KJ, Zhou P, Dabral SK, Pak E, Li W, Atwood SX, Whitson RJ, Chang AL, Li J, Oro AE, Chan JA, Kelleher JF, Segal RA. RAS/MAPK Activation Drives Resistance to Smo Inhibition, Metastasis, and Tumor Evolution in Shh Pathway-Dependent Tumors. Cancer Res. 2015 Sep 1;75(17):3623-35.


Pak E, MacKenzie EL, Zhao X, Pazyra-Murphy MF, Park PMC, Wu L, Shaw DL, Addleson EC, Cayer SS, Lopez BG, Agar NYR, Rubin LL, Qi J, Merk DJ, Segal RA. A large-scale drug screen identifies selective inhibitors of class I HDACs as a potential therapeutic option for SHH medulloblastoma. Neuro Oncol. 2019 Sep 6;21(9):1150-1163.


Zhao X, Pak E, Ornell KJ, Pazyra-Murphy MF, MacKenzie EL, Chadwick EJ, Ponomaryov T, Kelleher JF, Segal RA. A Transposon Screen Identifies Loss of Primary Cilia as a Mechanism of Resistance to SMO Inhibitors. Cancer Discov. 2017 Dec;7(12):1436-1449.