# EDGAR Filing Document

**Accession Number:** 0001724979
**File Stem:** 0001104659-23-005901
**Filing Date:** 2023-1
**Character Count:** 13827
**Document Hash:** 2099b77600b76a693a50c8dc0eb4d412
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-23-005901.hdr.sgml**: 20230123

**ACCESSION NUMBER**: 0001104659-23-005901

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 13

**CONFORMED PERIOD OF REPORT**: 20230123

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20230123

**DATE AS OF CHANGE**: 20230123

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Rain Oncology Inc.
- **CENTRAL INDEX KEY:** 0001724979
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 821130967
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-40356
- **FILM NUMBER:** 23545234

**BUSINESS ADDRESS:**
- **STREET 1:** 8000 JARVIS AVENUE
- **STREET 2:** SUITE 204
- **CITY:** NEWARK
- **STATE:** CA
- **ZIP:** 94560
- **BUSINESS PHONE:** (510) 953-5559

**MAIL ADDRESS:**
- **STREET 1:** 8000 JARVIS AVENUE
- **STREET 2:** SUITE 204
- **CITY:** NEWARK
- **STATE:** CA
- **ZIP:** 94560

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Rain Therapeutics Inc.
- **DATE OF NAME CHANGE:** 20171211

?xml version="1.0" encoding="utf-8"?

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**PURSUANT TO SECTION 13 OR 15(d)**

**OF THE SECURITIES EXCHANGE ACT OF 1934**

**Date of Report (Date of earliest event reported): January 23, 2023**

**Rain Oncology Inc.**

**(Exact Name of Registrant as Specified in its Charter)**

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-40356** | **82-1130967** |
| **(State or Other Jurisdiction**<br> **of Incorporation)** | **(Commission**<br> **File Number)** | **(IRS Employer**<br> **Identification No.)** |

---

**8000 Jarvis Avenue, Suite 204**

**Newark, CA 94560**

**(Address of Principal Executive Offices)**

**(510) 953-5559**

**(Registrant's telephone number, including area code)**

**Rain Therapeutics Inc.**

**(Former Name or Former Address, if Changed Since Last Report)**

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 210.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| **Title of each class** | **Trading<br> Symbol(s)** | **Name of each exchange<br> on which registered** |
| **Common Stock, par value $0.001 per share** | **RAIN** | **The Nasdaq Global Select Market** |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging growth company ⌧

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ◻

---

| | |
|:---|:---|
| **Item 7.01** | **Regulation FD Disclosure.** |

---

On January 23, 2023, Rain Oncology Inc. issued a press release announcing the publication of Phase 1 clinical data of milademetan in the Journal of Clinical Oncology.

The press release is attached hereto as Exhibit 99.1, which is furnished under Item 7.01 of this Current Report on Form 8-K and shall not be deemed to be "filed" for purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act, regardless of any general incorporation language in such filing.

---

| | |
|:---|:---|
| **Item 9.01** | **Financial Statements and Exhibits** |

---

(d) *Exhibits*. The following exhibit is being furnished herewith:

**<u>EXHIBIT INDEX</u>**

---

| | |
|:---|:---|
| **Exhibit<br> No.** | **Description** |
| [99.1](tm234208d1_ex99-1.htm) | [Press Release, dated January 23, 2023](tm234208d1_ex99-1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

---

**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | | |
|:---|:---|:---|
| Dated: January 23, 2023 | **Rain Oncology Inc.** | **Rain Oncology Inc.** |
|  | By: | /s/ Avanish Vellanki |
|  |  | Avanish Vellanki |
|  |  | *Chairman and Chief Executive Officer* |

---

## Exhibit 99.1

**Exhibit 99.1**

**Phase 1 Clinical Data of Milademetan Published in Journal of Clinical Oncology**

*– Intermittent dosing of milademetan, an inhibitor of the p53-MDM2 complex, potentially exhibits an avenue to address historical issues with cytopenias with this class of compounds–*

*– Phase 1 data in advanced dedifferentiated liposarcoma provides foundation for the registrational Phase 3 MANTRA trial –*

NEWARK, Calif., January 23, 2023 (GLOBE NEWSWIRE) -- Rain Oncology Inc. (NasdaqGS: RAIN), ("Rain"), a late-stage company developing precision oncology therapeutics with its lead product candidate, milademetan, an oral, small molecule inhibitor of the p53-MDM2 complex that reactivates p53, today announced the publication of a peer-reviewed article titled, "A First-in-Human Phase I Study of Milademetan, an MDM2 Inhibitor, in Patients with Advanced Liposarcoma, Solid Tumors or Lymphomas" in the *Journal of Clinical Oncology*. Phase 1 clinical data in the paper highlight the activity and tolerability using intermittent dosing of milademetan across a range of tumor types including dedifferentiated liposarcoma (DD LPS), which represented the largest proportion of patients enrolled in the study (n=53).

"An intermittent dosing schedule (260 mg qd, 3/14 days) of our highly selective inhibitor of the p53-MDM2 complex, milademetan, resulted in favorable safety and clinical activity in the Phase 1 trial in DD LPS patients," said Robert Doebele, MD, Ph.D., co-founder, president and chief scientific officer of Rain. "We view the prior data leveraging the intermittent dosing schedule as potentially offering a compelling risk/reward benefit, laying the foundation for our registrational Phase 3 MANTRA trial."

"Historical challenges with MDM2 inhibition identified cytopenias as a concern, for which intermittent dosing may provide a solution," said Richard Bryce, MBChB, Rain's chief medical officer. "The intermittent dosing schedule identified may provide for a more favorable tolerability profile that we would expect to translate across a multitude of future therapeutic indications."

**Key Article Highlights Include:**

&nbsp;&nbsp;&nbsp;&nbsp;· All liposarcoma patients enrolled in the Phase 1 trial exhibited the DD LPS subtype

&nbsp;&nbsp;&nbsp;&nbsp;· Among DD LPS patients in the Phase 1 trial, median progression-free survival (mPFS) outcomes were maintained with intermittent dosing
schedules (once daily [qd] on days 1-3 and 15-17 every 28 days; eg, 3/14 days) compared with extended (qd on days 1-21) / continuous (qd
on days 1-28) schedules:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ mPFS of patients across all doses/schedules (n=53): 7.2 months

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ mPFS of patients with 260 mg qd 3/14 intermittent schedule (n=16): 7.4 months

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ mPFS of previously treated patients with 260 mg qd 3/14 intermittent schedule (n=11): 8.0 months

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ mPFS of treatment-naïve patients in all doses/schedules (n=17): 14.6 months

&nbsp;&nbsp;&nbsp;&nbsp;· Although all tested DD LPS patients had MDM2 gene amplification (n=22), mPFS in DD LPS patients did not differ by levels of key biomarkers
including *MDM2* or *CDK4* copy number or by mRNA expression levels of *MDM2*, *CDK4*, or *MDM4*.

&nbsp;&nbsp;&nbsp;&nbsp;· The preferred intermittent dosing schedule of milademetan (260 mg qd 3/14 days) mitigates dose-limiting hematologic adverse events
while maintaining activity, leading to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ Marked reductions in occurrence and severity of grade 3/4 drug-related thrombocytopenia (15.8%; n=38) compared to extended/continuous
schedules (36.2%; n=69) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;▪ Fewer dose reductions (21.1%; n=8) and dose interruptions (15.8%; n=6) compared with extended/continuous schedules (23.3%; n=16 and
34.8%; n=24, respectively).

&nbsp;&nbsp;&nbsp;&nbsp;· Preliminary single-agent activity with milademetan in DD LPS prompted the ongoing, randomized Phase 3 MANTRA trial (NCT04979442),
with topline data anticipated in the first quarter of 2023.

**About Milademetan**

Milademetan (also known as RAIN-32) is an oral small molecule inhibitor of the p53-MDM2 complex that reactivates p53. Milademetan has demonstrated antitumor activity in an MDM2-amplified subtype of liposarcoma (LPS) and other solid tumors in a Phase 1 clinical trial, supported by a rationally designed dosing schedule to mitigate safety concerns and widen the potential therapeutic window of inhibition of the p53-MDM2 complex. Rain has completed enrollment in a Phase 3 trial of milademetan (MANTRA) in patients with LPS, and is evaluating milademetan in a Phase 2 tumor-agnostic basket trial in certain solid tumors (MANTRA-2). Rain anticipates commencing a Phase 1/2 clinical trial to evaluate the safety, tolerability and efficacy of milademetan in combination with Roche's atezolizumab in patients with loss of cyclin-dependent kinase inhibitor 2A (CDKN2A) and wildtype p53 advanced solid tumors (MANTRA-4), in the first quarter of 2023. Milademetan has received Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) for the treatment of LPS.

**About Rain Oncology Inc.**

Rain Oncology Inc. is a late-stage precision oncology company developing therapies that target oncogenic drivers to genetically select patients it believes will most likely benefit. This approach includes using a tumor-agnostic strategy to select patients based on their tumors' underlying genetics rather than histology. Rain's lead product candidate, milademetan, is a small molecule, oral inhibitor of the p53-MDM2 complex that reactivates p53. In addition to milademetan, Rain is also developing a preclinical program that is focused on inducing synthetic lethality in cancer cells by inhibiting RAD52.

**Forward Looking Statements**

Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements include statements regarding, among other things, Rain's ongoing and planned trials for milademetan, patient enrollment, timing for topline and interim data, including anticipated timing for topline data in the Phase 3 MANTRA trial, timing for the commencement of planned trials, and expected trial designs. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Words such as "plans," "will", "anticipates," "goal," "potential," "expects" and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Rain's current expectations and involve assumptions that may never materialize or may prove to be incorrect. Actual results could differ materially from those anticipated in such forward-looking statements as a result of various risks and uncertainties, which include, without limitation, risks and uncertainties associated with Rain's business in general and limited operating history, Rain's ability to execute on its strategy; Rain's reliance on third parties to conduct and support its preclinical studies and clinical trials, positive results from a clinical trial may not necessarily be predictive of the results of future or ongoing clinical studies; the effect of the COVID-19 pandemic on Rain's clinical trials and business operations, the impact of general economic, health, industrial or political conditions in the United States or internationally, the sufficiency of Rain's capital resources and its ability to raise additional capital, and the other risks described in Rain's Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent filings with the Securities and Exchange Commission. All forward-looking statements contained in this press release speak only as of the date on which they were made and are based on management's assumptions and estimates as of such date. Rain undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made, except as required by law.

**Media Contact**

Jordyn Temperato

LifeSci Communications

<u>jtemperato@lifescicomms.com</u>

**Investor Contact**

Daniel Ferry

LifeSci Advisors

+1.646.597.6989

<u>daniel@lifesciadvisors.com</u>