– On track to dose 15-20 patients with higher dose cNeT by year-end 2023 – – Clinical and translational science data update from the ongoing Phase I/IIa trials in NSCLC and melanoma expected in Q1 2024 with additional data available in mid-2024 – – Strong cash position of $140 million supports operations through 2025 – LONDON, Nov. 13, 2023 (GLOBE NEWSWIRE) — Achilles Therapeutics plc (NASDAQ: ACHL), a clinical-stage biopharmaceutical company developing AI-powered precision T cell therapies targeting clonal neoantigens to treat solid tumors, today announced its financial results for the quarter ended September 30, 2023, and recent business highlights. “We are pleased with progress across the scientific field that continues to demonstrate the importance of neoantigens as the most attractive targets in solid-tumor oncology. We believe that our proprietary capability to identify the most immunogenic clonal neoantigens, recently shared at ESGCT and SITC, puts us in a strong position with our clonal neoantigen-reactive T cell (cNeT) therapy and potentially other neoantigen targeting approaches,” said Dr Iraj Ali, Chief Executive Officer of Achilles Therapeutics. “Our Phase I/IIa clinical trials evaluating cNeT therapy for the treatment of advanced NSCLC (CHIRON) and metastatic malignant melanoma (THETIS) continue to progress and we are on track to dose patients in line with our previous guidance. We look forward to sharing our next clinical and translational data update in Q1 2024.” Recent Highlights Presented posters (Abstract 437, Abstract 1312) at the Society for Immunotherapy of Cancer (SITC) 38th Annual Meeting highlighting a significant dose boost of reactive CD8 and CD4 cNeT from the optimized VELOSTM manufacturing platform and the use of the PELEUS™ AI-powered bioinformatics platform for the identification and validation of immunogenic clonal tumor neoantigens.Presented posters (P459, P485, P507) at the European Society of Gene & Cell Therapy (ESGCT) 30th Annual Congress highlighting the favorable cNeT phenotypic properties and polyfunctionality critical for precision adoptive cell therapies and the expansion of cNeT from the blood of patients with cancer.Delivered an oral presentation at the mRNA Cancer Vaccines Summit highlighting neoRanker™, a new AI-based tool for the selection of immunogenic clonal tumor neoantigens for personalized therapies.Delivered oral presentations at the 5th Annual TIL Therapies Summit highlighting optimized manufacturing of AI-powered precision TIL therapies for solid cancer, and the potency and fitness of cNeT.Presented posters (P319, P407, P518) at the Seventh International Cancer Immunotherapy Conference (CICON23) highlighting a precision adoptive cell therapy process based on expansion of cNeT from blood of cancer patients. Financial Highlights Cash and cash equivalents: Cash and cash equivalents were $140.1 million as of September 30, 2023, as compared to $173.3 million as of December 31, 2022. The Company anticipates that its cash and cash equivalents are sufficient to fund its planned operations through 2025.Research and development (R&D) expenses: R&D expenses were $14.7 million for the third quarter ended September 30, 2023, an increase of $4.1 million compared to $10.6 million for the third quarter ended September 30, 2022. The increase was primarily driven by increased activity related to our ongoing clinical trials and overall R&D.General and administrative (G&A) expenses: G&A expenses were $4.4 million for the third quarter ended September 30, 2023, a decrease of $1.0 million compared to $5.4 million for the third quarter ended September 30, 2022. This decrease was primarily driven by lower professional fees, personnel costs and facilities spend. Net loss: Net loss for the third quarter ended September 30, 2023, was $16.7 million or $0.42 per share compared to $12.5 million or $0.32 per share for the third quarter ended September 30, 2022. About Achilles Therapeutics Achilles is a clinical-stage biopharmaceutical company developing AI-powered precision T cell therapies targeting clonal neoantigens: protein markers unique to the individual that are expressed on the surface of every cancer cell. The Company has two ongoing Phase I/IIa trials, the CHIRON trial in patients with advanced non-small cell lung cancer (NSCLC) and the THETIS trial in patients with recurrent or metastatic melanoma. Achilles uses DNA sequencing data from each patient, together with its proprietary PELEUS™ bioinformatics platform, to identify clonal neoantigens specific to that patient, and then develop precision T cell-based product candidates specifically targeting those clonal neoantigens. Forward Looking Statements This press release contains express or implied forward-looking statements that are based on our management’s belief and assumptions and on information currently available to our management. Forward-looking statements in this press release include, but are not limited to, statements regarding the timing of the Company’s clinical and translational data updates and the Company’s beliefs about recent data updates, and expectations related to the Company’s operating expenses and capital expense requirements. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to future events or our future operational or financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance, or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. The forward-looking statements in this press release represent our views as of the date of this press release. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should therefore not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this press release. For further information, please contact: Investors:Meru AdvisorsLee M. Sternlstern@meruadvisors.com Media:ICR ConsiliumSukaina Virji, Tracy Cheung, Emmalee Hoppe+44 (0) 203 709 5000achillestx@consilium-comms.com ACHILLES THERAPEUTICS PLC Condensed Consolidated Balance Sheets (Unaudited)(in thousands, except share and per share amounts)(expressed in U.S. Dollars, unless otherwise stated) September 30, December 31, 2023 2022 ASSETS Current assets: Cash and cash equivalents $140,138 $173,338 Prepaid expenses and other current assets 15,354 23,242 Total current assets 155,492 196,580 Non-current assets: Property and equipment, net 9,648 12,399 Operating lease right of use assets 7,013 8,081 Deferred tax assets 185 251 Restricted cash 33 33 Other assets 2,967 3,014 Total non-current assets 19,846 23,778 TOTAL ASSETS $175,338 $220,358 LIABILITIES AND SHAREHOLDERS’ EQUITY Current liabilities: Accounts payable $5,352 $5,187 Income taxes payable – 326 Accrued expenses and other liabilities 8,209 8,292 Operating lease liabilities-current 4,620 4,188 Total current liabilities 18,181 17,993 Non-current liabilities: Operating lease liabilities-non-current 2,731 4,388 Other long-term liability 941 933 Total non-current liabilities 3,672 5,321 Total liabilities 21,853 23,314 Commitments and contingencies (Note 12) Shareholders’ equity: Ordinary shares, £0.001 par value; 40,782,948 and 40,932,727 shares authorized, issued and outstanding at September 30, 2023 and December 31, 2022, respectively 54 54 Deferred shares, £92,451.851 par value, one share authorized, issued and outstanding at September 30, 2023 and December 31, 2022 128 128 Additional paid in capital 413,815 408,844 Accumulated other comprehensive loss (19,190) (21,695)Accumulated deficit (241,322) (190,287)Total shareholders’ equity 153,485 197,044 TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY $175,338 $220,358 ACHILLES THERAPEUTICS PLC Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)(in thousands, except share and per share amounts)(expressed in U.S. Dollars, unless otherwise stated) Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 OPERATING EXPENSES: Research and development $14,712 $10,597 $42,354 $38,387 General and administrative 4,384 5,437 13,387 17,162 Total operating expenses 19,096 16,034 55,741 55,549 Loss from operations (19,096) (16,034) (55,741) (55,549)OTHER INCOME, NET: Other income 2,389 3,599 4,692 8,499 Total other income, net 2,389 3,599 4,692 8,499 Loss before provision for income taxes (16,707) (12,435) (51,049) (47,050)Benefit (Provision) for income taxes 24 (41) 14 (70)Net loss (16,683) (12,476) (51,035) (47,120)Other comprehensive income: Foreign exchange translation adjustment (5,289) (18,147) 2,505 (45,126)Comprehensive loss $(21,972) $(30,623) $(48,530) $(92,246)Net loss per share attributable to ordinary shareholders—basic and diluted $(0.42) $(0.32) $(1.28) $(1.20)Weighted average ordinary shares outstanding—basic and diluted 40,066,922 39,313,764 39,900,910 39,104,866