Positive results from the pivotal phase 3 SIERRA trial in patients with relapsed or refractory acute myeloid leukemia

On February 23, 2023 Immedica’s partner Actinium Pharmaceuticals Inc. has reported results for the primary and secondary endpoints from its pivotal phase 3 SIERRA trial of Iomab-B in patients aged 55 and above with relapsed or refractory acute myeloid leukemia (r/r AML) with active disease (Press release, Immedica Pharma, FEB 23, 2023, View Source [SID1234627614]).

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The SIERRA trial met its primary endpoint of superior durable Complete Remission (dCR = CR or CRp (CR with incomplete platelet recovery) lasting ≥6 months after initial CR/CRp following hematopoietic stem cell transplantation HSCT) with a high degree of statistical significance (p<0.0001). The median overall survival (OS) was 6.4 months for Iomab-B and 3.2 months for the physician´s choice of conventional care arm. More importantly, of the 13 patients (22 %) who achieved dCR on the Iomab-B arm 92% were still alive at 1 year and 60% at 2 years, and hence long-term survivors. Iomab-B enabled access to HSCT with 100% engraftment in all patients receiving a therapeutic dose of Iomab-B. Only 14 of the 77 patients randomized to the conventional care arm achieved a CR on physician’s choice of standard therapy and could proceed to HSCT. None of them had a CR duration of ≥6 months (dCR). Iomab-B was well tolerated compared to conventional care.

Results from the SIERRA trial were presented at the Tandem Meetings: Transplantation & Cellular Therapy Meetings of the American Society for Transplantation and Cellular Therapy (ASTCT) and the Center for International Blood & Marrow Transplant Research (CIBMTR). The full abstract is found here: View Source

In April 2022, Immedica and Actinium Pharmaceuticals, Inc. entered a license and supply agreement for Iomab-B, where Immedica has the commercial rights in Europe, the Middle East, and North Africa.

Anders Edvell, CEO of Immedica commented: "We are very encouraged by these results. Iomab-B has the potential to significantly improve the outcomes in a patient population that is underserved by current therapies. We look forward to continuing our collaboration with Actinium to make Iomab-B available for patients in our territories".

SIERRA trial results

The SIERRA trial is a prospective, randomized, controlled phase 3 study comparing Iomab-B to physician’s choice of conventional therapy to patients ≥55 years of age with relapsed or refractory acute myeloid leukemia with active disease, a group of patients with dismal prognosis and few effective therapeutic options. Primary endpoint was the rate of dCR (≥ 6 months). Patients not achieving CR with conventional care could crossover (CO) to Iomab-B-based conditioning followed by HSCT. Forty patients from the conventional care arm actually crossed over. The outcome for CO patients receiving Iomab-B was similar to what was seen in the group randomized to Iomab-B.

SIERRA was conducted at 24 of the leading HSCT centers in the United States and Canada. SIERRA enrolled older, heavily pre-treated patients with active disease and high-risk characteristics who would not be offered HSCT in standard practice outside of a clinical trial and therefore have dismal survival outcomes of two to three months.

HSCT access and engraftment:

All patients (N=66) receiving the therapeutic dose of Iomab-B were able to access HSCT with 100% engraftment. Only 14 patients in the conventional care arm did eventually achieve a CR and could proceed to HSCT. The time from randomization to HSCT was more than doubled for these patients compared to patients transplanted after Iomab-B (median 29 vs. 66.5 days)

Primary endpoint – dCR:

Iomab-B met the primary endpoint of dCR, i.e., a CR (or CRp) with a duration of at least 6 months following initial CR after HSCT, with a high degree of statistical significance (p<0.0001)
22% of patients (13/59) in the per protocol analysis achieved dCR in the Iomab-B arm compared to 0% of patients on the control arm.
Secondary endpoints – event free survival and overall survival:

Iomab-B demonstrated significant improvement in EFS with a Hazard Ratio = 0.22, p<0.0001, which means Iomab-B reduced the probability of an event by 78%. Iomab-B numerically doubled the median overall OS compared to patients who were treated with conventional care without crossover (6.4 months vs 3.2 months).
A high percentage of patients achieving dCR after Iomab-B are long term survivors: 92% and 60% were still alive 1 and 2 years after initial CR respectively.
The median OS in the CO arm was 7.1 months.
Safety information:

Iomab-B was well tolerated compared to conventional care.
The incidence of sepsis was four times lower in the Iomab-B arm compared to patients undergoing HSCT in the control arm (6.1% vs 28.6%).

About Iomab-B
Iomab-B is an anti-CD-45 monoclonal antibody conjugated to the radioisotope 131I. CD45 is widely expressed on leukemia and immune cells including bone marrow progenitor stems cells. The radiation emitted from Iomab-B kills both the cells that the antibody binds to, and also the neighboring cells thereby delivering targeted radiation directly to leukemic cells and white blood cells in the myeloid tissue ablating the bone marrow while sparing healthy organs.

Iomab-B is a first-in-class targeted radiotherapy intended to improve patient access to potentially curative HSCT. Multiple studies have demonstrated increased survival in patients receiving HSCT, however, an overwhelming majority of patients with r/r AML do not receive HSCT as current approaches do not produce a remission, which is needed to advance to HSCT, or are too toxic.

Actinium intends to submit a Biologics License Application (BLA) seeking approval for Iomab-B in 2023 to address patients age 55+ with r/r AML with active disease. Iomab-B has been granted Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) and has patent protection into 2037. Iomab-B has also been granted Orphan Drug Designation by the European Medicines Agency (EMA) and Immedica will now start to prepare marketing approval applications relevant for the European territory.

MEI Pharma and Infinity Pharmaceuticals Announce Definitive Merger Agreement to Advance Three Promising Clinical Oncology Candidates

On February 23, 2023 MEI Pharma, Inc. (Nasdaq: MEIP) ("MEI"), a clinical-stage pharmaceutical company focused on advancing new therapies for cancer, and Infinity Pharmaceuticals, Inc. (Nasdaq: INFI) ("Infinity"), a clinical-stage biotechnology company developing eganelisib, a first-in-class, oral, immuno-oncology macrophage reprogramming drug candidate, reported that the companies entered into a definitive merger agreement for an all-stock transaction forming a company combining the expertise and resources of MEI and Infinity to advance a robust pipeline of three clinical-stage oncology drug candidates (Press release, Infinity Pharmaceuticals, FEB 23, 2023, View Source [SID1234627613]). All three clinical-stage development programs have the potential, in combination with current therapies, to overcome known resistance mechanisms and meaningfully improve patient outcomes.

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The combined company’s clinical-stage oncology development pipeline consists of three differentiated programs:

Eganelisib, an oral immuno-oncology macrophage reprogramming product candidate, which is planned to be evaluated in combination with the PD-1 targeted checkpoint inhibitor pembrolizumab (KEYTRUDA) in patients with head and neck squamous cell carcinoma (HNSCC);
Voruciclib, an oral CDK9 inhibitor, currently being studied in combination with venetoclax (VENCLEXTA) in patients with hematologic malignancies; and
ME-344, a novel tumor selective mitochondrial inhibitor targeting the OXPHOS pathway, to be evaluated in combination with bevacizumab (AVASTIN) in patients with relapsed colorectal cancer.
"We are very excited to enter into this agreement with Infinity given the strength of a combined organization that builds on each company’s potential. The combined organization will have three differentiated clinical-stage oncology assets, expected funding into mid-2025 to reach clinical data in all three programs, and a team with extensive oncology clinical development expertise. I believe these ingredients place the merged organization in a strong position to create value for all our stakeholders," said Daniel Gold, Ph.D., President and Chief Executive Officer of MEI Pharma. "The new company’s lead program, eganelisib, has already been tested in over 350 patients with demonstrated clinical activity in multiple settings, including in combination therapy with immune checkpoint inhibitors. Along with voruciclib and ME 344, this gives us three promising clinical-stage programs that we believe have significant potential to deliver improved therapeutic options for patients."

"With this planned merger, we are creating a company that is well capitalized to advance a differentiated clinical-stage therapeutic development pipeline leveraging an experienced drug development and leadership team," said Adelene Perkins, Chief Executive Officer and Chair of Infinity. "With data supporting multiple potential development paths for eganelisib, we have prioritized head and neck cancer based on our ability to leverage encouraging progression free survival data from this patient population in MARIO-1. Unfortunately, head and neck cancer remains an area of high unmet medical need with a relatively short PFS and overall survival in patients treated with checkpoint inhibitor monotherapy. Because of this, we prioritized the initiation of a randomized, controlled Phase 2 clinical study combining eganelisib with pembrolizumab in head and neck cancer patients which is intended to demonstrate improved clinical benefit."

"I am looking forward to leading the combined company which, beyond the promising clinical-stage pipeline, leverages the capabilities and resources of two organizations sharing a commitment to developing new oncology therapeutics. The combined company is built around extensive small molecule development experience based on solid science and backed by promising data," said David Urso, J.D., Chief Operating Officer and General Counsel of MEI Pharma, and the Chief Executive Officer of the combined company upon closing of the merger. "At closing, the combined company is projected to have a strong balance sheet of approximately $100 million which is expected to fund planned studies for our clinical candidates through mid-2025 with the potential to deliver near and long-term value for patients and shareholders."

About the Combined Clinical Pipeline Drug Candidates

The combined company’s pipeline includes three differentiated, clinical-stage, small molecule oncology therapeutic candidates:

Eganelisib: A potential first-in-class, oral, once-daily, immuno-oncology development candidate that selectively inhibits phosphoinositide-3-kinase gamma. Eganelisib has demonstrated encouraging clinical results and tolerability across a broad range of solid tumors in over 350 patients, including head and neck squamous cell carcinoma (HNSCC), metastatic triple-negative breast cancer (mTNBC), as well as urothelial, ovarian and melanoma cancers. The combined company plans to initiate in Q3 2023, subject to U.S. Food and Drug Administration review, a global, randomized, controlled Phase 2 clinical trial of eganelisib plus pembrolizumab vs pembrolizumab for the potential treatment of first line relapsed/metastatic head and neck squamous cell carcinoma. The primary endpoint of the Phase 2 study will be overall survival. In the second half of 2024 we plan to have initial data on safety and progression free survival.
Voruciclib: An orally administered Cyclin-Dependent Kinase 9 (CDK9) inhibitor being clinically investigated for hematological malignancies. CDK9 has important functions in cell cycle regulation, including the modulation of two therapeutic targets in cancer: myeloid leukemia cell differentiation protein (MCL1) and the MYC proto-oncogene protein, which regulate cell proliferation and growth. Voruciclib is currently being evaluated in a Phase 1b trial exploring dose and schedule in patients with acute myeloid leukemia (AML) and B-cell malignancies as a single-agent and in combination with venetoclax. The ongoing Phase 1b trial is expected to report initial results from the combination regimen around the end of 2023.
ME-344: A novel, parenteral, tumor selective mitochondrial inhibitor drug candidate targeting the OXPHOS pathway involved in the production of adenosine. Clinical investigation of ME-344 is focused on use in combination with the VEGF inhibitor bevacizumab (Avastin). Data reported from an investigator-initiated, multi-center, randomized study of ME-344 in combination with the VEGF inhibitor bevacizumab (Avastin) demonstrated biologic activity supporting further clinical investigation. Initiation of a Phase 1b trial is planned to evaluate ME-344 plus bevacizumab in patients with relapsed colorectal cancer in the first half of 2023. Data from the Phase 1b trial to support opening enrollment in an expansion cohort are expected to be reported around the end of 2023.
About the Proposed Merger

Under the terms of the merger agreement, Infinity will become a wholly owned subsidiary of MEI Pharma. Pursuant to an exchange ratio set forth in the merger agreement, the pre-merger MEI Pharma shareholders are expected to own approximately 58.0% and pre-merger Infinity shareholders are expected to own approximately 42.0% of the outstanding equity of the combined company immediately following the merger.

Subject to shareholder approval and the subsequent closing of the merger, the combined company is expected to be renamed and trade on the Nasdaq Stock Market. The combined company would be headquartered in San Diego, California and led by a team with extensive industry and oncology drug development expertise, including David Urso, Chief Executive Officer, Robert Ilaria, Jr., M.D., Chief Medical Officer, and Stéphane Peluso, Ph.D., Chief Scientific Officer. Daniel Gold, Ph.D., and Adelene Perkins, the current chief executive officers of MEI and Infinity, respectively, would serve on the Board of Directors of the combined company. The Board of Directors is expected to be composed of eight members, consisting of Mr. Norman C. Selby, currently Infinity’s Lead Independent Director, who will Chair the Board, Mr. Urso, Dr. Gold, Ms. Perkins, two additional members designated by MEI Pharma, one additional member designated by Infinity and one member mutually agreed upon by MEI Pharma and Infinity.

The merger agreement has been approved by the Boards of Directors of both companies. The merger is expected to close in mid-2023, subject to approvals by MEI Pharma and Infinity shareholders, respectively, and other customary closing conditions.

Torreya Capital, LLC is serving as financial advisor to MEI Pharma, and Morgan, Lewis & Bockius LLP is serving as legal counsel to MEI Pharma. Aquilo Partners, L.P. is serving as financial advisor to Infinity, and WilmerHale is serving as legal counsel to Infinity.

Conference Call and Webcast Information

MEI Pharma and Infinity Pharmaceuticals will host a conference call and webcast today at 8:00 a.m. ET to discuss the merger. To access the live call, please dial 1-833-974-2378 (United States) or 1-412-317-5771 (International). Please ask to join the MEI and Infinity merger conference call.

The conference call will also be webcast live here, as well as from the Events Calendar page in the Investors section of MEI Pharma’s website at www.meipharma.com and the Events & Presentations page in the Investors/Media section of Infinity’s website at www.infi.com. All participants are encouraged to join 10 minutes prior to the start time. An archived version of the webcast will be available on each company’s website for 30 days following the event.

IN8bio Presents Preclinical Data Showing Non-Signaling CAR Platform Targets Cancer Cells While Preserving Healthy Tissue

On February 23, 2023 IN8bio, a clinical-stage biopharmaceutical company discovering and developing innovative gamma-delta T cell therapies, reported the ability of its novel non-signaling gamma-delta CAR-T platform (nsCAR) to selectively target leukemic cells while preserving healthy B cells (Press release, In8bio, FEB 23, 2023, View Source [SID1234627612]). The findings were presented by Dr. Lawrence Lamb, IN8bio’s Chief Scientific Officer, during a Plenary session titled "Leveraging the Nexus of the Immune System with Gamma-Delta CAR-T Cells" at the 6th CAR-TCR Summit Europe on February 23rd.

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The current generation of CAR-T technology eliminates the target antigen regardless of whether it is expressed on tumor or healthy tissues. However, IN8bio’s nsCAR platform uses the innate immune recognition of gamma-delta T cells to distinguish between tumor and healthy tissue, offering a targeted but potentially less toxic approach. In a 48-hour in vitro cytotoxicity experiment, the nsCAR platform demonstrated a greater than 15x difference in killing between leukemic cells and healthy B cells (E:T=2:1, 79.7% versus 5.2%) when both express the CD19 target antigen.

The nsCAR platform is also engineered to express the cytokine interleukin-15 (IL-15) to enhance cellular persistence and the ability to target and kill tumor cells over time. The platform has the potential to broaden the utilization of CAR technology for previously "undruggable" solid and liquid tumor targets.

"This powerful approach could be used in indications such as acute myeloid leukemia (AML) and solid tumor cancers where on-target, off-tumor expression would result in toxicities with significant risks to patients," said Lawrence Lamb, Ph.D., co-founder and Chief Scientific Officer of IN8bio. "While CD19 was a preclinical proof-of-concept, we look forward to advancing the nsCAR platform into solid tumor indications as well as promising targets for AML, such as CD33."

The data presented supports the potential of IN8bio’s nsCAR platform to revolutionize the development of future CAR-T therapies, with the findings demonstrating the ability of the novel approach to distinguish between tumor cells and healthy tissue. The presentation is available on the company’s website at View Source

About INB-300

INB-300, our non-signaling CAR gamma-delta T cell platform, includes several preclinical product candidates combining our expertise in gamma-delta T cells and genetic engineering. These nsCAR constructs lack signaling domains in order to take advantage of the unique properties of gamma-delta T cells to differentiate between healthy and tumor tissues. IN8bio is advancing new nsCAR constructs against multiple targets to treat both solid and liquid tumors.

Immunocore to Report Fourth Quarter and Full Year 2022 Earnings and Host Call on March 1, 2023

On February 23, 2023 Immunocore Holdings plc (Nasdaq: IMCR), a commercial-stage biotechnology company pioneering the development of a novel class of T cell receptor (TCR) bispecific immunotherapies designed to treat a broad range of diseases, including cancer, autoimmune and infectious diseases, reported that it will report full year 2022 results, before the US markets open on Wednesday, March 1, 2023 (Press release, Immunocore, FEB 23, 2023, View Source [SID1234627611]). Following the announcement, the Company will host a live teleconference and webcast at 8:00 a.m. ET (1:00 p.m. GMT) to discuss their financial results and provide a business and portfolio update.

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Audio Webcast
The call will be made available via webcast by visiting the Events & Presentations section on Immunocore’s website. A replay of this webcast will be available for 90 days.

Conference Call Details:
Domestic (toll-free): 877-405-1239
International (toll): +1 201-389-0851

Guardant Health Reports Fourth Quarter and Full Year 2022 Financial Results and Provides 2023 Outlook

On February 23, 2023 Guardant Health, Inc. (Nasdaq: GH), a leading precision oncology company focused on helping conquer cancer globally through use of its proprietary tests, vast data sets and advanced analytics, reported financial results for the quarter and full year ended December 31, 2022 (Press release, Guardant Health, FEB 23, 2023, View Source [SID1234627610]).

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Fourth Quarter 2022 Financial Highlights
•Revenue of $126.9 million for the fourth quarter of 2022, an increase of 17% over the fourth quarter of 2021.
•Reported 36,000 tests to clinical customers and 8,200 tests to biopharmaceutical customers in the fourth quarter of 2022, representing an increase of 41% and 24%, respectively, over the fourth quarter of 2021.
Full Year 2022 Financial Highlights
•Revenue of $449.5 million for the full year 2022, an increase of 20% over the full year 2021.
•Reported 124,800 tests to clinical customers and 26,000 tests to biopharmaceutical customers in the full year 2022, representing an increase of 42% and 40%, respectively, over the full year 2021.
Recent Highlights
•Demonstrated 83% sensitivity and 90% specificity in pivotal ECLIPSE study evaluating Shield for colorectal cancer detection. Separately, Guardant Shield LDT has shown greater than 90% adherence in real world settings.
•Announced FDA approval for Guardant360 CDx as companion diagnostic for ORSERDU for treatment of patients with ESR1 mutations in ER+, HER2- advanced or metastatic breast cancer.
•Obtained coverage for Guardant360 CDx tests in lung and breast cancer from United Healthcare.
•Introduced Guardant Galaxy suite of advanced AI analytics in partnership with Lunit to enhance our portfolio of cancer tests starting with the Guardant360 TissueNext PD-L1 test, shown to improve biomarker detection by >20% in NSCLC.
"2022 marked another year of great progress at Guardant Health. We achieved record revenues and volumes during the year, launched new offerings in minimal residual disease with multi cancer Reveal and expanded market access for our tests. We also launched our Smart Liquid Biopsy platform, which we believe will drive the next chapter of growth for our oncology business and enable significant R&D efficiency and operating leverage. With the approval of our first companion diagnostic in breast cancer and expanded payor coverage, we are poised for continued strong growth in the year ahead," said Helmy Eltoukhy, co-founder and co-CEO.
"In December, we reported successful results in our pivotal ECLIPSE study for colorectal cancer screening with 83% sensitivity at 90% specificity. With over 90% of individuals completing the blood-based screening test, Shield significantly improves adherence rates and adds an important new option for patients and healthcare providers to boost screening rates, detect more cancers and save countless lives," said AmirAli Talasaz, co-founder and co-CEO. "We intend to complete our submission to FDA in the first quarter of 2023 as we continue our research and development efforts in screening for lung and additional cancers."
Fourth Quarter 2022 Financial Results
Revenue was $126.9 million for the three months ended December 31, 2022, a 17% increase from $108.1 million for the three months ended December 31, 2021. Precision oncology revenue grew 28%, driven predominantly by an increase in clinical testing volume and biopharma sample volume, which grew 41% and 24%, respectively, over the prior year period. Development services and other revenue decreased by 33%, primarily due to a one-time catch-up royalty payment that was recognized in the fourth quarter of 2021.
Gross profit, or total revenue less cost of precision oncology testing and cost of development services and other, was $79.8 million for the fourth quarter of 2022, an increase of $5.1 million from $74.7 million for the corresponding prior year period. Gross margin, or gross profit divided by total revenue, was 63%, as compared to 69% for the corresponding prior year period.
Operating expenses were $225.9 million for the fourth quarter of 2022, as compared to $172.9 million for the corresponding prior year period, an increase of 31%. Non-GAAP operating expenses were $201.2 million for the fourth quarter of 2022, as compared to $146.2 million for the corresponding prior year period.

Net loss attributable to Guardant Health, Inc. common stockholders was $139.9 million for the fourth quarter of 2022, as compared to $90.9 million for the corresponding prior year period. Net loss per share attributable to Guardant Health, Inc. common stockholders was $1.36 for the fourth quarter of 2022, as compared to $0.89 for the corresponding prior year period. Non-GAAP net loss was $119.6 million for the fourth quarter of 2022, as compared to $70.4 million for the corresponding prior year period. Non-GAAP net loss per share was $1.17 for the fourth quarter of 2022, as compared to $0.69 for the corresponding prior year period.
Adjusted EBITDA loss was $109.8 million for the fourth quarter of 2022, as compared to a $64.6 million loss for the corresponding prior year period.
Full Year 2022 Financial Results
Revenue was $449.5 million for the year ended December 31, 2022, a 20% increase from $373.7 million for the year ended December 31, 2021. Precision oncology revenue grew 29%, driven predominantly by an increase in clinical testing volume and biopharma sample volume, which grew 42% and 40%, respectively, over the prior year period. Development services and other revenue decreased by 17%, primarily due to the change in collaboration projects with biopharmaceutical customers for companion diagnostic development and regulatory approval services, and discontinuation of our Guardant-19 tests in August 2021, partially offset by revenues earned from licensing our technologies, and providing data services during the year ended December 31, 2022.
Gross profit, or total revenue less cost of precision oncology testing and cost of development services and other, was $293.2 million for 2022, an increase of $42.5 million from $250.7 million for the corresponding prior year period. Gross margin, or gross profit divided by total revenue, was 65%, as compared to 67% for the corresponding prior year period.
Operating expenses were $837.6 million for 2022, as compared to $661.7 million for the corresponding prior year period, an increase of 27%. Non-GAAP operating expenses were $736.6 million for 2022, as compared to $506.8 million for the corresponding prior year period.
Net loss attributable to Guardant Health, Inc. common stockholders was $654.6 million for 2022, as compared to $405.7 million for the corresponding prior year period. Net loss per share attributable to Guardant Health, Inc. common stockholders was $6.41 for 2022, as compared to $4.00 for the corresponding prior year period. Non-GAAP net loss was $435.4 million for 2022, as compared to $251.7 million for the corresponding prior year period. Non-GAAP net loss per share was $4.26 for 2022, as compared to $2.48 for the corresponding prior year period.
Adjusted EBITDA loss was $403.4 million for 2022, as compared to a $231.5 million loss for the corresponding prior year period.
Cash, cash equivalents and marketable debt securities were $1.0 billion as of December 31, 2022.
2023 Guidance
Guardant Health expects full year 2023 revenue to be in the range of $525 million to $540 million, representing growth of 17% to 20% compared to full year 2022.
We expect full year 2023 operating expenses to be below full year 2022, and free cash outflow to be approximately $350 million in 2023.
Webcast Information
Guardant Health will host a conference call to discuss the fourth quarter and full year 2022 financial results after market close on Thursday, February 23, 2023 at 1:30 pm Pacific Time / 4:30 pm Eastern Time. A webcast of the conference call can be accessed at View Source The webcast will be archived and available for replay for at least 90 days after the event.

Non-GAAP Measures
Guardant Health has presented in this release certain financial information in accordance with U.S. Generally Accepted Accounting Principles (GAAP) and also on a non-GAAP basis, including non-GAAP cost of precision oncology testing, non-GAAP research and development expense, non-GAAP sales and marketing expense, non-GAAP general and administrative expense, non-GAAP loss from operations, non-GAAP net loss, non-GAAP net loss attributable to Guardant Health, Inc., common stockholders, non-GAAP net loss per share attributable to Guardant Health, Inc. common stockholders, basic and diluted, and Adjusted EBITDA.
We define our non-GAAP measures as the applicable GAAP measure adjusted for the impacts of stock-based compensation and related employer payroll tax payments, changes in estimated fair value of noncontrolling interest liability, adjustments relating to redeemable noncontrolling interest, contingent consideration, acquisition related expenses, amortization of intangible assets, fair value adjustments on marketable equity securities, impairment of other assets, and other non-recurring items.
Adjusted EBITDA is defined as net loss attributable to Guardant Health, Inc. common stockholders adjusted for interest income; interest expense; other income (expense), net; provision for income taxes; depreciation and amortization expense; stock-based compensation expense and related employer payroll tax payments; changes in estimated fair value of noncontrolling interest liability; adjustments relating to redeemable noncontrolling interest and contingent consideration; and, if applicable in a reporting period, acquisition-related expenses, and other non-recurring items.
We believe that the exclusion of certain income and expenses in calculating these non-GAAP financial measures can provide a useful measure for investors when comparing our period-to-period core operating results, and when comparing those same results to that published by our peers. We exclude certain other items because we believe that these income (expenses) do not reflect expected future operating expenses. Additionally, certain items are inconsistent in amounts and frequency, making it difficult to perform a meaningful evaluation of our current or past operating performance. We use these non-GAAP financial measures to evaluate ongoing operations, for internal planning and forecasting purposes, and to manage our business.
These non-GAAP financial measures are not intended to be considered in isolation from, as substitute for, or as superior to, the corresponding financial measures prepared in accordance with GAAP. There are limitations inherent in non-GAAP financial measures because they exclude charges and credits that are required to be included in a GAAP presentation, and do not present the full measure of our recorded costs against its revenue. In addition, our definition of the non-GAAP financial measures may differ from non-GAAP measures used by other companies.