Developing Precision therapies for genetically defined diseases Corporate Presentation Q4 2020 Forward Looking Statements and Risk Factors This presentation and the accompanying oral commentary contain forward-looking st

therapies for genetically defined diseases Corporate Presentation Q4 2020Exhibit 99.1 Developing Precision therapies for genetically defined diseases Corporate Presentation Q4 2020

Forward Looking Statements and Risk Factors

This presentation and the accompanying oral commentary contain forward-looking statements that involve risks, uncertainties and assumptions. If the risks or uncertainties ever materialize or the assumptions prove incorrect, our results may differ

materially from those expressed or implied by such forward looking statements. All statements other than statements of historical fact could be deemed forward-looking, including, but not limited to, any statements of the plans, strategies, and

objectives of management for future operations, including our clinical development and commercialization plans; any projections of financial information; any statement about historical results that may suggest trends for our business; any statement

of expectation or belief regarding future events; potential markets or market size, technology developments, our clinical product pipeline, clinical data or the implications thereof, enforceability of our intellectual property rights, competitive

strengths or our position within the industry; any statements regarding the anticipated benefits of our collaborations or other strategic transactions; and any statements of assumptions underlying any of the items mentioned. These statements are

based on estimates and information available to us at the time of this presentation and are not guarantees of future performance. Actual results could differ materially from our current expectations as a result of many risks and uncertainties,

including but not limited to, risks associated with: the potential impacts of raising additional capital, including dilution to our existing stockholders, restrictions our operations or requirements that we relinquish rights to our technologies or

product candidates; business interruptions resulting from the coronavirus disease outbreak or similar public health crises, which could cause a disruption of the development of our product candidates and adversely impact our business; the success,

cost, and timing of our product development activities and clinical trials; the timing of our planned regulatory submissions to the FDA for our product candidate PLX9486 and feedback from the FDA as to our plans; our ability to obtain and maintain

regulatory approval for our PLX9486 product candidate and any other product candidates we may develop, and any related restrictions, limitations, and/or warnings in the label of an approved product candidate; the potential for our identified

research priorities to advance our PLX9486 product candidate; the ability to license additional intellectual property relating to our product candidates from third-parties and to comply with our existing license agreements and collaboration

agreements; the ability and willingness of our third-party research institution collaborators to continue research and development activities relating to our product candidates; our ability to commercialize our products in light of the intellectual

property rights of others; our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates; the scalability and commercial viability of our manufacturing

methods and processes; the commercialization of our product candidates, if approved;our plans to research, develop, and commercialize our product candidates; our ability to attract collaborators with development, regulatory, and commercialization

expertise; our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates; among others. For a further description of the risks and uncertainties that could cause actual results to differ

from those expressed in these forward-looking statements, as well as risks relating to our business in general, see our periodic filings filed from time to time with the Securities and Exchange Commission. Unless as required by law, we assume no

obligation and do not intend to update these forward-looking statements or to conform these statements to actual results or to changes in our expectations. All of Cogent Biosciences ("Cogent") product candidates are investigational

product candidates and their safety and efficacy have not yet been established. Cogent has not obtained marketing approval for any product, and there is no certainty that any marketing approvals will be obtained or as to the timelines on which they

will be obtained. Any data pertaining to Cogent product candidates is interim data and may include investigator-reported interim data for which Cogent has not yet independently reviewed the source data. The interim data may not be representative of

the final results that may be obtained in the corresponding trials and results from earlier trials may not be representative of results obtained in later trial or pivotal trials. 2Forward Looking Statements and Risk Factors This presentation

and the accompanying oral commentary contain forward-looking statements that involve risks, uncertainties and assumptions. If the risks or uncertainties ever materialize or the assumptions prove incorrect, our results may differ materially from

those expressed or implied by such forward looking statements. All statements other than statements of historical fact could be deemed forward-looking, including, but not limited to, any statements of the plans, strategies, and objectives of

management for future operations, including our clinical development and commercialization plans; any projections of financial information; any statement about historical results that may suggest trends for our business; any statement of expectation

or belief regarding future events; potential markets or market size, technology developments, our clinical product pipeline, clinical data or the implications thereof, enforceability of our intellectual property rights, competitive strengths or our

position within the industry; any statements regarding the anticipated benefits of our collaborations or other strategic transactions; and any statements of assumptions underlying any of the items mentioned. These statements are based on estimates

and information available to us at the time of this presentation and are not guarantees of future performance. Actual results could differ materially from our current expectations as a result of many risks and uncertainties, including but not

limited to, risks associated with: the potential impacts of raising additional capital, including dilution to our existing stockholders, restrictions our operations or requirements that we relinquish rights to our technologies or product candidates;

business interruptions resulting from the coronavirus disease outbreak or similar public health crises, which could cause a disruption of the development of our product candidates and adversely impact our business; the success, cost, and timing of

our product development activities and clinical trials; the timing of our planned regulatory submissions to the FDA for our product candidate PLX9486 and feedback from the FDA as to our plans; our ability to obtain and maintain regulatory approval

for our PLX9486 product candidate and any other product candidates we may develop, and any related restrictions, limitations, and/or warnings in the label of an approved product candidate; the potential for our identified research priorities to

advance our PLX9486 product candidate; the ability to license additional intellectual property relating to our product candidates from third-parties and to comply with our existing license agreements and collaboration agreements; the ability and

willingness of our third-party research institution collaborators to continue research and development activities relating to our product candidates; our ability to commercialize our products in light of the intellectual property rights of others;

our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates; the scalability and commercial viability of our manufacturing methods and processes; the

commercialization of our product candidates, if approved;our plans to research, develop, and commercialize our product candidates; our ability to attract collaborators with development, regulatory, and commercialization expertise; our expectations

regarding our ability to obtain and maintain intellectual property protection for our product candidates; among others. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these

forward-looking statements, as well as risks relating to our business in general, see our periodic filings filed from time to time with the Securities and Exchange Commission. Unless as required by law, we assume no obligation and do not intend to

update these forward-looking statements or to conform these statements to actual results or to changes in our expectations. All of Cogent Biosciences ("Cogent") product candidates are investigational product candidates and their safety

and efficacy have not yet been established. Cogent has not obtained marketing approval for any product, and there is no certainty that any marketing approvals will be obtained or as to the timelines on which they will be obtained. Any data

pertaining to Cogent product candidates is interim data and may include investigator-reported interim data for which Cogent has not yet independently reviewed the source data. The interim data may not be representative of the final results that may

be obtained in the corresponding trials and results from earlier trials may not be representative of results obtained in later trial or pivotal trials. 2

Cogent Biosciences: Emerging Leader in Precision Medicines for

Genetically Defined Diseases PLX9486, a potential best-in-class KIT exon 17 inhibitor, has demonstrated promising clinical efficacy and safety results in a Phase 1/2 clinical trial in patients with gastrointestinal stromal tumors (GIST), along with

accelerated timelines to proof-of-concept in systemic mastocytosis 1H 2021 2H 2021 Broad clinical development plan Initiate ASM clinical trial designed to move PLX9486 rapidly Initiate randomized GIST clinical trial to high unmet need patient

populations Initiate ISM clinical trial 2021+ Strategy Create pipeline of additional highly selective, potent compounds Cogent is well capitalized with $129.4 million as of September 30, 2020 3Cogent Biosciences: Emerging Leader in Precision

Medicines for Genetically Defined Diseases PLX9486, a potential best-in-class KIT exon 17 inhibitor, has demonstrated promising clinical efficacy and safety results in a Phase 1/2 clinical trial in patients with gastrointestinal stromal tumors

(GIST), along with accelerated timelines to proof-of-concept in systemic mastocytosis 1H 2021 2H 2021 Broad clinical development plan Initiate ASM clinical trial designed to move PLX9486 rapidly Initiate randomized GIST clinical trial to high unmet

need patient populations Initiate ISM clinical trial 2021+ Strategy Create pipeline of additional highly selective, potent compounds Cogent is well capitalized with $129.4 million as of September 30, 2020 3

PLX9486: Next Generation

KIT exon 17 InhibitorPLX9486: Next Generation KIT exon 17 Inhibitor

PLX9486 is a Highly Selective and Potent KIT Mutant Inhibitor with

Potential to Demonstrate Best-in-Class Clinical Profile PLX9486 Encouraging Clinical Activity 12 months mPFS demonstrated with combination of Specifically targets KIT exon 17 D816V PLX9486 + sunitinib in heavily pre-treated GIST patients

mutations Selective versus other targets including wild-type KIT, PDGFR , VEGFR2, FLT3 Attractive Emerging Safety Profile and FMS Well tolerated with no significant safety signals across 50+ patients in single agent & combination

dosing Worldwide rights to compound exclusively 1 licensed from Plexxikon Potential Best-in-Class KIT exon 17 inhibitor 2 Patent protection through at least 2033 KIT D816V inhibition supports future studies in systemic mastocytosis

and GIST; safety results support potential for broad use 1 Plexxikon is eligible for mid- to high- single-digit royalties and additional development milestones. License includes rights to PLX0206, an additional selective KIT inhibitor in preclinical

development 5 2 Does not include available patent term extensionPLX9486 is a Highly Selective and Potent KIT Mutant Inhibitor with Potential to Demonstrate Best-in-Class Clinical Profile PLX9486 Encouraging Clinical Activity 12 months mPFS

demonstrated with combination of Specifically targets KIT exon 17 D816V PLX9486 + sunitinib in heavily pre-treated GIST patients mutations Selective versus other targets including wild-type KIT, PDGFR , VEGFR2, FLT3 Attractive

Emerging Safety Profile and FMS Well tolerated with no significant safety signals across 50+ patients in single agent & combination dosing Worldwide rights to compound exclusively 1 licensed from Plexxikon Potential Best-in-Class KIT

exon 17 inhibitor 2 Patent protection through at least 2033 KIT D816V inhibition supports future studies in systemic mastocytosis and GIST; safety results support potential for broad use 1 Plexxikon is eligible for mid- to high- single-digit

royalties and additional development milestones. License includes rights to PLX0206, an additional selective KIT inhibitor in preclinical development 5 2 Does not include available patent term extension

PLX9486 Designed as Potent and Selective KIT exon 17 D816V Inhibitor

PLX9486 is a Type I Inhibitor designed to selectively bind the active conformation of mutant KIT Comparable potency observed relative to avapritinib with potential selectivity advantages Limited blood-brain-barrier penetration and no

CNS toxicities identified in preclinical studies Potency Selectivity IC50 (nM) IC50 (nM) Enzyme Assay PLX9486 PLX9486 Avapritinib >5000* c-Kit (wt) KIT D814Y autophosphorylation 12 22 c-Kit (D816V) 1.125 a (murine P815 cells) FMS 602.4

b BA/F3 KIT D816V growth 12 13.5 KDR/VEGFR2 >5000* b KIT D816V kinase activity (Reaction Bio) 1.125 0.4143 PDGFR >5000* a Comparison of PLX9486 data with previously published avapritinib data

PDGFR (D842V) 104.3 b Direct comparison within experiments using non GMP syntheses

Note: No head to head clinical trials have been conducted between PLX9486 and avapritinib. *Highest concentration tested in biochemical assay 6PLX9486

Designed as Potent and Selective KIT exon 17 D816V Inhibitor PLX9486 is a Type I Inhibitor designed to selectively bind the active conformation of mutant KIT Comparable potency observed relative to avapritinib with potential selectivity

advantages Limited blood-brain-barrier penetration and no CNS toxicities identified in preclinical studies Potency Selectivity IC50 (nM) IC50 (nM) Enzyme Assay PLX9486 PLX9486 Avapritinib >5000* c-Kit (wt) KIT D814Y autophosphorylation 12

22 c-Kit (D816V) 1.125 a (murine P815 cells) FMS 602.4 b BA/F3 KIT D816V growth 12 13.5 KDR/VEGFR2 >5000* b KIT D816V kinase activity (Reaction Bio) 1.125 0.4143 PDGFR >5000* a Comparison of PLX9486 data with previously published

avapritinib data PDGFR (D842V) 104.3 b Direct comparison within experiments using non GMP syntheses Note: No head to head clinical trials have been conducted between PLX9486 and avapritinib. *Highest concentration tested in

Dual-conformation KIT Inhibition Drives Tumor Regression in

Heterogeneous GIST mouse models Ex11 (W557_K558del), Ex17 (N822K) Ex13 (K642E), Ex17 (D823Y) 7Dual-conformation KIT Inhibition Drives Tumor Regression in Heterogeneous GIST mouse models Ex11 (W557_K558del), Ex17 (N822K) Ex13 (K642E), Ex17 (D823Y)

Systemic Mastocytosis&

KIT exon 17 D816V mutationsSystemic Mastocytosis& KIT exon 17 D816V mutations

Significant Unmet Need Remains for Neurological Headache, brain fog,

Systemic Mastocytosis Patients cognitive dysfunction, anxiety, depression Systemic Mastocytosis Systemic Disease driven by over-accumulation of mast Anaphylaxis cells across various internal organs in the body Cutaneous (skin) Advanced

Systemic Mastocytosis (ASM) Flushing of the face/neck/chest, hives, skin rashes, itching with or without rash Median survival of approximately 3.5 years FDA approved drug, Rydapt (Midostaurin), Gastrointestinal broad spectrum

TKI, challenging tolerability Diarrhea, nausea, vomiting, abdominal pain, bloating, gastroesophageal reflux disease (GERD) Indolent and Smoldering Mastocytosis (ISM) Significantly impacts quality of life No approved therapies:

current treatments Other include H1 and H2 anti-histamines, mast cell Cardiovascular Skeletal Light-headedness, syncope (fainting), stabilizers, leukotriene inhibitors Bone/muscle pain, rapid heart rate, chest pain, low blood osteopenia,

osteoporosis pressure, high blood pressure at Gynecological reaction start, blood pressure instability Uterine cramps, bleeding Ear/Nose/Throat/Respiratory Urinary Nasal itching and congestion, throat Bladder irritability, frequent itching and

swelling, wheezing, voiding shortness of breathSignificant Unmet Need Remains for Neurological Headache, brain fog, Systemic Mastocytosis Patients cognitive dysfunction, anxiety, depression Systemic Mastocytosis Systemic Disease driven by

over-accumulation of mast Anaphylaxis cells across various internal organs in the body Cutaneous (skin) Advanced Systemic Mastocytosis (ASM) Flushing of the face/neck/chest, hives, skin rashes, itching with or without rash Median survival of

approximately 3.5 years FDA approved drug, Rydapt (Midostaurin), Gastrointestinal broad spectrum TKI, challenging tolerability Diarrhea, nausea, vomiting, abdominal pain, bloating, gastroesophageal reflux disease (GERD) Indolent and

Smoldering Mastocytosis (ISM) Significantly impacts quality of life No approved therapies: current treatments Other include H1 and H2 anti-histamines, mast cell Cardiovascular Skeletal Light-headedness, syncope (fainting),

stabilizers, leukotriene inhibitors Bone/muscle pain, rapid heart rate, chest pain, low blood osteopenia, osteoporosis pressure, high blood pressure at Gynecological reaction start, blood pressure instability Uterine cramps, bleeding

Ear/Nose/Throat/Respiratory Urinary Nasal itching and congestion, throat Bladder irritability, frequent itching and swelling, wheezing, voiding shortness of breath

Systemic Mastocytosis (SM): Primarily Driven by KIT exon 17 D816V

Mutations KIT exon 17 D816V mutation is 1 detected in >90% of SM patients o Occurs within the activation loop domain and causes a conformational change in the enzymatic pocket of the receptor o This conformational change results in ligand

independent constitutive activation of KIT and leads to increased proliferation Inhibition of KIT exon 17 mutations has shown clinical activity in both ASM and ISM 1 10 https://www.nejm.org/doi/full/10.1056/NEJMoa1513098Systemic Mastocytosis (SM):

Primarily Driven by KIT exon 17 D816V Mutations KIT exon 17 D816V mutation is 1 detected in >90% of SM patients o Occurs within the activation loop domain and causes a conformational change in the enzymatic pocket of the receptor o This

conformational change results in ligand independent constitutive activation of KIT and leads to increased proliferation Inhibition of KIT exon 17 mutations has shown clinical activity in both ASM and ISM 1 10

Large, Yet Not Well Understood Population of SM Patients Systemic

Mastocytosis: Estimated prevalence in the U.S. is 20,000-30,000 patients ISM Significant unmet medical need Comprises upwards of for clinically active, well tolerated 1 90% of all cases of SM treatment options for this patient population ASM 1

11 https://www.sciencedirect.com/science/article/abs/pii/S0145212619300566Large, Yet Not Well Understood Population of SM Patients Systemic Mastocytosis: Estimated prevalence in the U.S. is 20,000-30,000 patients ISM Significant unmet medical

need Comprises upwards of for clinically active, well tolerated 1 90% of all cases of SM treatment options for this patient population ASM 1 11 https://www.sciencedirect.com/science/article/abs/pii/S0145212619300566

PLX9486 Positioned to Move Rapidly Into ASM and ISM Clinical Studies

Pre-clinical KIT selectivity and potency along with clinical experience - safety + target engagement Phase 2 start as single agent in Phase 2 start as single agent in Advanced Indolent Systemic Mastocytosis (ASM) Systemic Mastocytosis (ISM)

(1H'2021) (2H'2021) Serum tryptase level is used as diagnostic marker for SM patients and considered to reflect the burden of mast cells will provide a well understood and accepted marker for assessing clinical proof of