A drug discovery leader and molecular pharmacologist with 20+ years advancing small-molecule therapeutics from target validation through candidate nomination — building discovery biology functions, screening platforms, and the teams that run them.
Dr. Reza Beheshti Zavareh is a molecular pharmacologist and drug discovery leader with more than twenty years of experience spanning academic research, biotechnology, and pharmaceutical organizations. His work has centered on advancing small-molecule therapeutics from target validation through lead optimization and candidate nomination, with deep expertise in screening cascade design, mechanistic characterization, and the disease-relevant cellular models that guide compound progression and portfolio decisions.
His career spans Princess Margaret Cancer Centre, Calibr and The Scripps Research Institute, Janssen Pharmaceutical Companies of Johnson & Johnson, Ferring Research Institute, Trotana Therapeutics, and currently Montai Therapeutics — a trajectory that has given him a working fluency in how discovery science operates differently across academic institutes, global pharma, and venture-backed biotech, and what it takes to translate strategy into execution in each setting.
He has built and led multidisciplinary discovery biology teams, designed and scaled high-throughput and high-content screening platforms, and partnered consistently with medicinal chemistry, computational sciences, DMPK, and translational biology to accelerate design-make-test cycles. He continues to lead from the bench while shaping scientific strategy and organizational priorities — a combination increasingly rare at the seniority his roles have reached.
At Trotana Therapeutics, Dr. Beheshti Zavareh built the discovery biology and molecular pharmacology function from the ground up as Associate Director — establishing the strategy, infrastructure, and operating model for small-molecule programs spanning RNA biology, oncology, and immunology. He directed multiple discovery programs from target validation through candidate nomination, defining the stage-gate criteria and pharmacology packages that governed progression decisions, and recruited and managed a multidisciplinary team of five scientists and associates.
That mandate extended beyond science. He presented program strategy and key decisions directly to executive leadership and the Board, contributing to portfolio prioritization at the organizational level. He served as site Safety Officer, building a safety-first laboratory culture through training, BSL-2 compliance oversight, and risk assessment. And he provided structured coaching and career development to scientists and research associates across multiple concurrent programs — developing them, in his words, into independent project leaders rather than long-term direct reports.
At Janssen, the mandate was different but the pattern was the same: establish capability that did not yet exist. He built and scaled high-throughput flow cytometry as a discovery platform supporting hit identification, lead optimization, mechanism-of-action studies, and translational pharmacology across immunology, neuroscience, infectious disease, and virology — then trained and managed the scientists and research associates who would run it after he moved on.
Few scientists at the director level remain genuinely hands-on across the full span of modern drug discovery: target-based and phenotypic screening, high-throughput biochemical assays, high-content imaging, high-throughput flow cytometry, biophysical characterization, translational pharmacology, and now AI-enabled discovery. Dr. Beheshti Zavareh has operated at depth in each of these domains rather than delegating them — a breadth that shapes how he designs screening cascades and where he places disease-relevant complexity within them.
His core expertise includes assay design from target validation through candidate nomination, screening cascade architecture and stage-gate decision frameworks, hit identification and lead optimization, SAR support and compound profiling, and mechanism-of-action studies built on biophysical, biochemical, and cell-based platforms. In cancer biology and immuno-oncology, his work spans hematologic and solid tumor signaling, cancer metabolism and glycobiology, tumor microenvironment interactions, T-cell exhaustion, and immune checkpoint pathways including PD-1/PD-L1 and CTLA-4. In inflammation and translational immunology, his experience covers gastrointestinal, cutaneous, and B-cell-driven disease models, integrating histology, cytokine analysis, and translational phenotyping into program-level decisions.
This breadth is what allows him to design screening cascades that integrate biochemical, biophysical, high-throughput, and disease-relevant cellular assays into a single coherent decision framework — rather than treating each as an isolated technical exercise.
Dr. Beheshti Zavareh's publication record reflects the same continuum his career has spanned — from doctoral work establishing N-glycosylation as a functional regulator of cancer cell migration and metastasis (Cancer Research, 2008; PLoS One, 2012), through postdoctoral contributions at Calibr and Scripps on serine biosynthesis inhibition (PNAS, 2016) and a Cell Chemical Biology study demonstrating that HSP90 inhibition modulates immune checkpoint protein expression with direct relevance to checkpoint blockade combination strategies (2020).
More recent contributions include the identification of small-molecule inhibitors for the NK cell receptor NKG2D (PNAS, 2023) and a contribution to a 2024 Science publication on myeloid reprogramming via JAK inhibition to enhance checkpoint blockade therapy — work situated at the leading edge of immuno-oncology combination strategy. Across 24 publications and more than 1,460 citations, the throughline is consistent: mechanistic rigor applied to questions with direct therapeutic relevance.
Selected publications: Zak J. et al., "Myeloid reprogramming by JAK inhibition enhances checkpoint blockade therapy." Science, 2024 · Thompson A.A. et al., "Identification of small-molecule inhibitors for NKG2D." PNAS, 2023 · Beheshti Zavareh R. et al., "HSP90 inhibition enhances cancer immunotherapy by modulating surface expression of immune checkpoint proteins." Cell Chemical Biology, 2020
As Principal Scientist, Early Discovery Biology at Montai Therapeutics, Dr. Beheshti Zavareh leads biological and molecular pharmacology strategy for immunology discovery programs within a machine-learning-enabled platform, guiding target progression from validation through early in vivo evaluation. He defines the integrated assay cascades, biomarker strategies, and progression criteria that link in vitro pharmacology, SAR interpretation, and in vivo endpoints — and establishes disease-relevant primary-cell and patient-derived co-culture models to improve translational fidelity and compound prioritization.
A core part of the role is mentoring and training scientists in advanced flow cytometry, laboratory automation, and AI-enabled discovery workflows, and serving as the internal expert for flow-cytometry-based ligand and receptor binding, receptor occupancy, and functional assays — including SOP design, quality control, and CRO oversight. He partners directly with medicinal chemistry, computational, PK/PD, and data science teams to integrate mechanistic and modeling insight into program decisions and portfolio prioritization.
While fully engaged at Montai Therapeutics, I take on a small number of consulting engagements each year where the scientific challenge is genuinely interesting and the fit is right. My focus is on early discovery problems that require both strategic thinking and deep experimental knowledge.
I'm reachable for scientific conversations, collaboration, consulting enquiries, peer review, and speaking invitations. I respond thoughtfully, though not always immediately.
Twenty years of hands-on platform building — from a Biomek FX in a Toronto hematology lab to designing a first-of-its-kind high-throughput flow cytometry system at Janssen, and now integrating experimental biology with machine learning at Montai.
The most important decision in early drug discovery is not which compound to screen. It is which question to ask — and which biological system is capable of answering it honestly.
Phenotypic drug discovery and target-based drug discovery are not competing philosophies. They are complementary instruments, and the art lies in knowing when to reach for each. Target-based approaches offer mechanistic clarity, rational optimization, and throughput — but they assume the target is the right one, that an isolated biochemical system reflects the cell, and that the cell reflects the disease. Those assumptions fail more often than the field admits.
Phenotypic approaches test in complex biological systems, preserve whole-cell fidelity, and remain agnostic to mechanism — which is precisely their strength when the disease mechanism is incompletely understood, when the target is a pathway rather than a protein, or when the biology is multifactorial. Cancer, neurodegeneration, and complex immune dysregulation have historically yielded more first-in-class drugs through phenotypic routes than through target-based ones. That is not an accident.
But phenotypic screening is not simply "more biological." It demands more sophisticated assay design, more rigorous controls, and a clearer hypothesis about what the phenotype means mechanistically. An uninterpretable readout is not informative — it is noise at scale. The discipline is building cellular systems that are disease-relevant without being so complex they become uninterpretable, and that are scalable without sacrificing the biological fidelity that makes them worth running.
The decision between phenotypic and target-based is therefore not ideological — it is contextual. It depends on what is known about the target, how well the disease mechanism is understood, what translational models exist, and at what stage of the program certainty about mechanism is needed. The answer is almost always a hybrid: use target-based methods to establish biochemical proof-of-concept and drive SAR efficiency, while incorporating disease-relevant cellular systems earlier than convention suggests — not as validation endpoints, but as decision-making tools that shape which compounds enter optimization in the first place. Strategically placing high-content phenotypic assays earlier in the cascade improves the quality of SAR decisions, increases confidence in mechanism, and aligns lead series with downstream pharmacodynamic and efficacy models before the program has sunk resources into the wrong series.
Training in the University of Toronto's Department of Hematology instills a particular discipline. Clinical flow cytometry demands panel reproducibility at a standard wet-lab research cytometry rarely meets.
Two decades of cytometry breadth — from analytical benchtop instruments to high-throughput screening cytometers — have produced genuine expertise in platform selection, panel design, compensation and unmixing strategy, QC frameworks, and the translation of cytometry readouts into pharmacological conclusions. The right cytometer for a given biology is a scientific decision, not a procurement one.
A defining early experience was working with a pre-commercial version of the IQue Screener (Intellicyt/Sartorius) before it had a commercial name or established workflows. Building HT cytometry methods from scratch — before field standards existed — became a recurring theme, culminating in the Janssen HT-FC platform design.
The instrument generates images. The science lives in deciding what to measure from them — a decision that cannot be undone after the experiment runs.
Experience spans the full arc of the field's development, from early ArrayScan campaigns at Calibr to confocal Opera Phenix workflows and morphological profiling with Cell Painting. The discipline is not operating the microscope; it's designing the assay before a single plate is imaged.
Cell Painting represents a philosophical shift in how imaging is used in drug discovery. Rather than asking "does compound X activate pathway Y?", it asks "what does compound X do to the cell — globally, without prior hypothesis?" Six-channel morphological profiling generates thousands of features per cell. Applied to mechanism-of-action studies, it reveals polypharmacology, toxicity signatures, and pathway engagement that target-focused assays miss entirely.
Most scientists encounter automation as something that already exists when they arrive. Reza has repeatedly been the person who built it.
His first liquid handler was a Beckman Coulter Biomek FX — encountered in the University of Toronto's Department of Hematology. Learning a platform at that stage means internalizing something deeper than the protocol: how pipetting errors propagate, how dead volume behaves across tip types, how a CV of 3% in a 384-well plate means something entirely different from 3% in a 96-well plate.
At Calibr/Scripps, scale changed everything. The GNF Systems dispenser — purpose-built for 1536-well HTS — and the Labcyte Echo acoustic liquid handler together enabled compound dispensing at volumes previously impractical. The Agilent Bravo filled the gap for flexible cell-based workflows. At Janssen, the HighRes Biosolutions (HRB) modular robotic platform orchestrated multi-instrument integration — the backbone of the HT flow cytometry platform.
The plate reader is the workhorse of biochemical HTS. Knowing which reader to reach for — and which detection mode fits the assay biology — is the difference between a clean Z′ and a noise floor.
AI in biology is only as good as the experimental design that generated its training data. The scientist who built the platform is the one who can ensure the model has something real to learn from.
Engagement with AI/ML spans three distinct application layers, each requiring different expertise and each carrying specific failure modes when the underlying data is flawed.
A screening cascade is only as trustworthy as the data infrastructure underneath it. Most discovery biologists treat data management as an afterthought delegated to informatics; this has been a core operating competency throughout my career.
Running HTS, HT-FC, and high-content campaigns at scale means generating data volumes that cannot be managed in spreadsheets. Fluency in statistical computing and the registration, analysis, and decision-support platforms that pharma and biotech organizations run on has been essential to translating raw plate data into defensible SAR and progression decisions — and to ensuring that data is connected and queryable across the organization rather than trapped in silos.