Cullinan Oncology Provides Corporate Update and Reports Second Quarter 2022 Financial Results Completed agreement for strategic collaboration to jointly develop and commercialize CLN-081 with Taiho Pharmaceutical Present

Cullinan Oncology Provides Corporate Update and

Reports Second Quarter 2022 Financial Results

Completed agreement for strategic collaboration to jointly develop and commercialize

CLN-081 with Taiho Pharmaceutical

Presented updated Phase 1/2a data for CLN-081 at the 100mg BID dose showing median duration of response greater than 21 months and median progression-free survival of 12 months at the American Society for Clinical Oncology (ASCO) Annual Meeting

Cash and investments of $656 million1 as of June 30, 2022 expected to provide runway through 2026.

August 10, 2022 (GLOBE NEWSWIRE) Cullinan Oncology, Inc. (Nasdaq: CGEM), a biopharmaceutical company focused on developing a diversified pipeline of targeted therapeutic candidates across multiple modalities for patients

with cancer, today reported on recent and upcoming business highlights and announced its financial results for the second quarter ended June 30, 2022.

In the second quarter of 2022, Cullinan Oncology demonstrated significant portfolio advancement, including the closing of our agreement with Taiho

Pharmaceutical for CLN-081, an oral presentation for CLN-081 at the American Society of Clinical Oncology (ASCO) 2022 Annual Meeting, and continued progression of our

pipeline of potential first-in-class and best-in-class oncology assets. These

achievements demonstrate our commitment to creating new standards of care for patients with unmet need, said Nadim Ahmed, Chief Executive Officer of Cullinan Oncology.

We are pleased with the continued strengthening of CLN-081 s clinical profile, Ahmed continued.

Updated data released at ASCO highlighted a high response rate, favorable safety and tolerability, and improving durability of response from the ongoing Phase 1/2a study for patients with EGFR exon 20 insertion mutation non-small-cell lung cancer. Financially, the closing of the Taiho transaction for CLN-081 has extended our cash runway through 2026, giving us the financial flexibility to

accelerate and expand the development of our diverse pipeline as well as obtain promising new oncology assets. Looking ahead, we continue to advance our earlier-stage programs, including CLN-619 and CLN-049, with initial Phase 1 data readouts expected by mid-2023, as well as CLN-617 and

CLN-978, for which we anticipate IND filings in the first half of next year.

Portfolio Highlights

Second Quarter 2022 Financial Results

About Cullinan Oncology

Cullinan Oncology, Inc. (NASDAQ:

CGEM) is a biopharmaceutical company dedicated to creating new standards of care for patients with cancer. We innovate without borders to find the most promising clinic-ready cancer therapies, whether from our own discovery efforts or through

exceptional engagement with our academic and industry partners. Anchored in a deep understanding of immuno-oncology and translational cancer medicine, we leverage our scientific excellence in small molecules and biologics to create differentiated

ideas, identify unique targets, and select the optimal modality to develop transformative therapeutics across cancer indications. Powered by our novel research model, we push conventional boundaries from candidate selection to cancer therapeutic,

applying rigorous early experimentation to fast-

track only the most promising assets to the clinic and ultimately commercialization. As a result, our diversified pipeline is strategically built with assets that activate the immune system or

inhibit key oncogenic drivers across a wide range of modalities, each with the potential to be the best or first in their class.

Our people possess deep

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Forward-Looking Statements

This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. These forward-looking

statements include, but are not limited to, express or implied statements regarding Cullinan s beliefs and expectations regarding our preclinical and clinical development plans and timelines, clinical trial designs, clinical and therapeutic

potential, and strategy of our product candidates; our ability to evaluate strategic opportunities to accelerate development timelines; our ability to optimize the impact of our collaborations and license agreements with external parties; our

ability to continue our growth; our receipt of escrowed funds related to our transaction with Taiho Pharmaceutical; and our expectations regarding our use of capital. The words anticipate, believe, continue,

could, estimate, expect, hope, intend, may, plan, potential, predict, project, target, should,

would, and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

Any forward-looking statements in this press release are based on management s current expectations and beliefs of future events and are subject to known

and unknown risks and uncertainties that may cause our actual results, performance or achievements to be materially different from any expressed or implied by the forward-looking statements. These risks include, but are not limited to, the

following: uncertainty regarding the timing and results of regulatory submissions; success of our clinical trials and preclinical studies; risks related to our ability to protect and maintain our intellectual property position; risks related to

manufacturing, supply, and distribution of our product candidates; risks related to the impact of COVID-19 affecting countries or regions in which we have operations or do business, including potential

negative impacts on our employees, customers, supply chain and production as well as global economies and financial markets; the risk that any one or more of our product candidates, including those that are

co-developed, will not be successfully developed and commercialized; the risk that the results of preclinical studies or clinical studies will not be predictive of future results in connection with future

studies; and success of any collaboration, partnership, license or similar agreements. These and other important risks and uncertainties discussed in our filings with the Securities and Exchange Commission, including under the caption Risk

Factors in our most recent Annual Report on Form 10-K and subsequent filings with the SEC, could cause actual results to differ materially from those indicated by the forward-looking statements made in

this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change, except to the extent required by law. These

forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release. Moreover, except as required by law, neither Cullinan nor any other person assumes responsibility for the

accuracy and completeness of the forward-looking statements included in this press release. Any forward-looking statement included in this press release speaks only as of the date on which it was made.

Cullinan Oncology, Inc.

Condensed Consolidated Balance Sheets

Cullinan Oncology, Inc.

Consolidated Statements of Operations

(in thousands, except per share amounts)