•

Dose Expansion Portion of Phase 1 Trial to Commence by Year-End. The Company remains on track to commence the expansion portion of its Phase 1 trial of its lead product candidate, PRT543, which is designed to be a potent, selective, and oral inhibitor of PRMT5, in select solid tumor cohorts during the fourth quarter of 2020 and in select myeloid malignancy cohorts in early 2021. The expansion cohorts will include patients with adenoid cystic carcinoma (ACC), myelofibrosis (MF), genomically-selected myelodysplastic syndrome (MDS), and homologous recombination deficient positive (HRD+) tumors. Preliminary data from the dose escalation portion of the trial demonstrated early signs of clinical activity and tolerability, including a durable confirmed complete response (CR) in a patient with HRD+ high grade serous ovarian cancer who had received seven prior lines of therapy. The Company anticipates obtaining initial clinical data from these expansion cohorts in the first half of 2021 and presenting these data at medical meetings in 2021.

•

Dose Escalation Ongoing in Phase 1 Trial in Patients with Advanced Solid Tumors and Recurrent High-Grade Gliomas. The dose escalation portion of the Company’s Phase 1 trial of its second clinical product candidate, PRT811, which is designed to be a potent, selective, and brain

penetrant PRMT5 inhibitor, in patients with advanced solid tumors, including glioblastoma multiforme (GBM) and primary central nervous system lymphomas (PCNSL), remains ongoing. To date, the trial has demonstrated early signs of clinical activity and tolerability. The previously disclosed refractory GBM patient whose tumor had demonstrated a 66% reduction on monotherapy PRT811 has subsequently undergone a follow-up MRI at week 16 confirming a partial response (PR) per RANO (response assessment in neuro-oncology) criteria. The Company expects to commence the dose expansion portion of the trial in the first half of 2021, with data expected by the end of 2021.

•

Dosed First Patient in Phase 1 Trial of MCL1 Inhibitor PRT1419 for the Treatment of Relapsed/Refractory Hematologic Malignancies. In September 2020, Prelude announced dosing of the first patient in its first-in-human Phase 1 open-label, multicenter, dose-escalation study of PRT1419 in patients with relapsed/refractory hematologic malignancies. PRT1419, the Company’s third clinical candidate, is designed to be an orally available, potent, and selective MCL1 inhibitor.

•

Completed Initial Public Offering (IPO). In September 2020, Prelude closed its IPO of 9,573,750 shares of common stock, including the full exercise of the underwriters’ option to purchase up to 1,248,750 additional shares of common stock, at a public offering price of $19.00 per share. Aggregate gross proceeds to Prelude were approximately $181.9 million, before deducting underwriting discounts and commissions and other offering expenses of $15.3 million.

•

Strengthened Board of Directors with Two New Appointments. In August 2020, the Company announced the appointment of Mardi C. Dier and Victor Sandor, M.D., both highly accomplished industry veterans, to its Board of Directors.

•

Cash and cash equivalents: Cash and cash equivalents as of September 30, 2020 were $234.8 million.

•

Research and Development (R&D) Expenses: For the third quarter of 2020, R&D expenses increased by $9.8 million to $15.3 million compared to $5.5 million for the third quarter of 2019. The increase was mainly due to increased clinical research costs for the PRT543 and PRT811 clinical trials and increased costs associated with the initiation of the clinical trial for PRT1419, which began in the third quarter of 2020. Prelude also incurred an increase in chemistry, manufacturing, and other costs for those trials.

•

General and Administrative (G&A) Expenses: For the third quarter of 2020, G&A expenses increased by $1.5 million to $2.9 million compared to $1.4 million for the third quarter of 2019. The increase was primarily due to an increase in personnel related expense due to increases in employee headcount and an increase in professional fees as Prelude expanded its operations to support its research and development efforts and incurred additional costs to operate as a public company.

•

Net Loss: For the third quarter of 2020, net loss was $16.8 million, or $5.25 per share, compared to a net loss of $6.7 million, or $3.93 per share, for the third quarter of 2019.

Three Months Ended September 30,

(in thousands, except share and per share data)

2020

2019

Operating expenses:

Research and development

$

15,293

$

5,490

General and administrative

2,851

1,394

Total operating expenses

18,144

6,884

Loss from operations

(18,144

)

(6,884

)

Other income, net

1,384

150

Net loss

$

(16,760

)

$

(6,734

)

Per share information:

Net loss per share of common stock, basic and diluted

$

(5.25

)

$

(3.93

)

Weighted average common shares outstanding, basic

   and diluted

3,194,471

1,713,371

Balance Sheets
(unaudited)

(in thousands, except share data)

September 30,

2020

December 31,

2019

Assets

Current assets:

Cash and cash equivalents

$

234,792

$

18,879

Prepaid expenses and other current assets

3,269

1,345

Total current assets

238,061

20,224

Property and equipment, net

1,620

1,647

Total assets

$

239,681

$

21,871

Liabilities, convertible preferred stock and stockholders’ equity (deficit)

Current liabilities:

Capital lease obligation

$

—

$

258

Accounts payable

5,074

1,974

Accrued expenses and other current liabilities

6,285

2,603

Total current liabilities

11,359

4,835

Other liabilities

15

5

Total liabilities

11,374

4,840

Convertible preferred stock, $0.0001 par value:

Series A convertible preferred stock: No shares and 13,574,008 shares authorized at September 30, 2020 and December 31, 2019, respectively; no shares and 11,736,119 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively

—

36,595

Series B convertible preferred stock: No shares and 18,500,000 shares authorized at September 30, 2020 and December 31, 2019; No shares and 7,628,846 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively

—

29,848

Series C convertible preferred stock: no shares authorized, issued or outstanding at September 30, 2020 and December 31, 2019

—

—

Total convertible preferred stock

—

66,443

Stockholders’ equity (deficit):

Voting common stock, $0.0001 par value: 487,149,741 and 42,000,000 shares authorized at September 30, 2020 and December 31, 2019, respectively; 32,593,010 and 3,161,653 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively

3

—

Non-voting common stock, $0.0001 par value; 12,850,259 and no shares authorized at September 30, 2020 and December 31, 2019, respectively; 11,110,371 and no shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively

1

—

Additional paid-in capital

316,479

1,085

Accumulated deficit

(88,176

)

(50,497

)

Total stockholders’ equity (deficit)

228,307

(49,412

)

Total liabilities, convertible preferred stock and stockholders’ equity (deficit)

$

239,681

$

21,871