Myriad Genetics Receives FDA Approval of the MyChoice CDx Test as the Companion Diagnostic for Zejula (niraparib) for Patients with Ovarian Cancer

Rhea-AI Impact

(High)

Rhea-AI Sentiment

(Neutral)

Rhea-AI Summary

Myriad Genetics (NASDAQ: MYGN) announced FDA approval of the MyChoice CDx Test as the companion diagnostic for Zejula (niraparib) in advanced ovarian cancer in the United States. The approval is based on final PRIMA trial data and establishes MyChoice CDx as the only FDA-authorized CDx for Zejula.

The test uses next-generation sequencing to assess BRCA1/2 (including large rearrangements) and a tumor genomic instability score (LOH, TAI, LST) to determine HRD status for treatment decisions.

Positive

FDA approval confirms MyChoice CDx as Zejula companion diagnostic in the US
Only FDA-approved companion diagnostic for Zejula in the United States
Approval based on final PRIMA trial data supporting clinical validity
Comprehensive NGS-based assay assessing BRCA1/2 and tumor genomic instability (LOH, TAI, LST)

Negative

Approval and Zejula indications are specified for the United States only

News Market Reaction – MYGN

-2.93%

8 alerts

-2.93% News Effect

+2.5% Peak Tracked

-14.5% Trough Tracked

-$14M Valuation Impact

$471.28M Market Cap

0.2x Rel. Volume

On the day this news was published, MYGN declined 2.93%, reflecting a moderate negative market reaction. Argus tracked a peak move of +2.5% during that session. Argus tracked a trough of -14.5% from its starting point during tracking. Our momentum scanner triggered 8 alerts that day, indicating moderate trading interest and price volatility. This price movement removed approximately $14M from the company's valuation, bringing the market cap to $471.28M at that time.

Data tracked by StockTitan Argus on the day of publication.

Key Figures

HRD+ prevalence: Nearly 50% of advanced ovarian cancer patients

1 metrics

HRD+ prevalence Nearly 50% of advanced ovarian cancer patients Share of patients with HRD-positive tumors mentioned in the release

Market Reality Check

Price: $4.59 Vol: Volume 1,407,045 is below...

normal vol

$4.59 Last Close

Volume Volume 1,407,045 is below the 20-day average of 1,988,149, suggesting no outsized trading interest into this FDA approval. normal

Technical Shares at $4.59 are trading below the 200-day MA of $6.11 and sit 55.52% under the 52-week high of $10.32, though still 22.07% above the 52-week low of $3.76.

Peers on Argus

MYGN is down 1.5% while key diagnostics peers FLGT, CDNA, CSTL, and NEO show gai...

MYGN is down 1.5% while key diagnostics peers FLGT, CDNA, CSTL, and NEO show gains between 0.08% and 2.62%, with only PSNL lower at -2.16%. The mixed but mostly positive peer tape contrasts with MYGN’s decline, indicating a stock-specific reaction rather than a broad sector move.

Historical Context

5 past events · Latest: Mar 02 (Positive)

Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Mar 02	Product launch	Positive	+5.6%	Launch of Precise MRD ctDNA test with initial community oncologists.
Feb 24	Clinical data	Positive	+1.1%	Six ASCO‑GU abstracts highlighting performance of oncology tests.
Feb 23	Earnings & guidance	Positive	+1.1%	Q4 and 2025 results with reiterated 2026 revenue and margin guidance.
Feb 19	Analytical validation	Positive	+0.2%	FirstGene prenatal screen validation showing high sensitivity and specificity.
Feb 16	Earnings scheduling	Neutral	+0.2%	Announcement of timing for Q4 and full‑year 2025 earnings call.

Pattern Detected

Recent news and clinical/ product milestones have generally seen small but consistently positive next-day price reactions.

Recent Company History

Over the past month, Myriad has reported several supportive developments: commercial launch of its Precise MRD ctDNA test on Mar 2, 2026, positive oncology data presentations at ASCO‑GU, and analytical validation of the FirstGene prenatal screen. Q4 and full‑year 2025 results reiterated 2026 guidance, and an earnings date announcement preceded these updates. Each event saw modest positive price moves, so today’s FDA companion diagnostic approval extends a sequence of clinically oriented catalysts.

Regulatory & Risk Context

Active S-3 Shelf · $200,000,000

Shelf Active

Active S-3 Shelf Registration 2026-02-24

$200,000,000 registered capacity

An effective shelf registration filed on February 24, 2026 allows Myriad Genetics to offer up to $200,000,000 of various securities over time for general corporate purposes, including operations, R&D, debt repayment, or acquisitions. Actual dilution or leverage effects depend on if and how future offerings are executed.

Market Pulse Summary

This announcement highlights FDA approval of MyChoice CDx as the companion diagnostic for Zejula in ...

Analysis

This announcement highlights FDA approval of MyChoice CDx as the companion diagnostic for Zejula in advanced ovarian cancer, reinforcing Myriad’s role in comprehensive HRD testing. It follows recent product launches, validation data, and reiterated 2026 guidance, suggesting a steady stream of oncology‑focused catalysts. Investors may watch adoption trends for MyChoice CDx, progress of newer tests like Precise MRD and FirstGene, and any future use of the $200,000,000 shelf for growth initiatives.

Key Terms

companion diagnostic, parp inhibitor, homologous recombination deficiency, next generation sequencing, +4 more

8 terms

companion diagnostic medical

"approved the MyChoice® CDx Test as the Companion Diagnostic (CDx) for Zejula"

A companion diagnostic is a medical test designed to identify which patients are likely to benefit from a specific drug or medical treatment, much like a key that shows whether a particular lock will open. For investors, these tests matter because they can increase a drug’s chances of approval and market uptake, create a separate revenue stream, and reduce commercial risk by matching treatments to the patients most likely to respond.

parp inhibitor medical

"Zejula® (niraparib), a PARP inhibitor from GSK, for patients"

A PARP inhibitor is a type of drug that blocks a protein cells use to repair damaged DNA, making it harder for cancer cells to survive and multiply. For investors, these drugs matter because regulatory approvals, trial results, patent status, and competition directly affect potential sales, company valuations and partnership opportunities — think of a PARP inhibitor as a targeted tool that can make existing cancer treatments more effective and create commercial value if proven safe and effective.

homologous recombination deficiency medical

"determined homologous recombination deficiency (HRD) status and was used"

A condition in which a cell’s ability to fix certain types of DNA damage is impaired, like a zipper that can’t close properly after being pulled apart. Investors care because tumors with this flaw are often more sensitive to specific drugs and diagnostic tests, making related treatments, companion diagnostics, and clinical trial results potentially decisive for a company’s drug value and future revenue.

next generation sequencing medical

"status by leveraging next generation sequencing technology to conduct"

A collection of advanced laboratory methods that read and map large amounts of DNA or RNA quickly and at lower cost than older techniques; think of it as scanning thousands of pages of a book at once instead of reading one page at a time. Investors care because it accelerates drug development, enables precise diagnostics and personalized treatments, and can create recurring revenue from tests, instruments, and data services as adoption expands.

genomic instability score medical

"and tumor genomic instability score (GIS) that includes loss"

A genomic instability score is a single-number measure that summarizes how many and how severe the DNA errors and rearrangements are in a tumor’s cells. Think of it like a car’s check-engine light turned into a score: higher values mean the genome is more damaged or disordered. Investors watch this because the score can predict which patients may respond to certain cancer drugs, guide clinical trial design, and affect the commercial value of diagnostics and therapies.

loss of heterozygosity medical

"score (GIS) that includes loss of heterozygosity (LOH), telomeric"

Loss of heterozygosity occurs when one of the two gene copies a cell normally carries is lost or disabled, leaving only a single copy to do the job — like losing one instruction sheet from a two‑copy manual. For investors, it matters because this genetic change is often linked to cancer development, can alter how well targeted therapies or diagnostics work, and therefore influences the clinical value and commercial prospects of drugs and tests.

telomeric allelic imbalance medical

"includes loss of heterozygosity (LOH), telomeric allelic imbalance (TAI)"

Telomeric allelic imbalance is a measurable pattern of DNA damage near the ends of chromosomes that signals a cell’s inability to properly repair certain kinds of genetic breaks. Investors care because it is used as a clinical biomarker to predict which patients are likely to respond to DNA-repair-targeting therapies and to stratify clinical trials; clearer biomarker results can influence a drug’s approval chances, market size, and commercial value.

large-scale state transitions medical

"telomeric allelic imbalance (TAI) and large-scale state transitions (LST)"

A genomic biomarker that measures the number of large chromosomal breaks or rearrangements in a tumor’s DNA, reflecting how unstable the cancer genome is. Like counting deep potholes on a road to judge overall damage, a high count suggests the tumor may be more likely to respond to certain DNA-repair-targeting drugs and can influence clinical trial design, regulatory decisions and a therapy’s commercial prospects — information investors use to assess risk and potential market value.

AI-generated analysis. Not financial advice.

03/17/2026 - 04:05 PM

Approval reinforces Myriad’s leadership in comprehensive HRD testing and establishes MyChoice CDx as the only FDA-approved companion diagnostic for Zejula in the United States

SALT LAKE CITY, March 17, 2026 (GLOBE NEWSWIRE) -- Myriad Genetics, Inc., (NASDAQ: MYGN), a leader in molecular diagnostic testing and precision medicine, today announced that the U.S. Food and Drug Administration (FDA) has approved the MyChoice^® CDx Test as the Companion Diagnostic (CDx) for Zejula^® (niraparib), a PARP inhibitor from GSK, for patients with advanced ovarian cancer.

This approval is based on final data from the PRIMA trial, where the MyChoice CDx Test determined homologous recombination deficiency (HRD) status and was used to stratify advanced ovarian cancer patients.

The MyChoice CDx is the only FDA-approved companion diagnostic test in the United States to identify patients with HRD-positive status eligible for treatment with Zejula. The test determines HRD status by leveraging next generation sequencing technology to conduct a comprehensive assessment of BRCA1/2 genes -- including large rearrangements -- and tumor genomic instability score (GIS) that includes loss of heterozygosity (LOH), telomeric allelic imbalance (TAI) and large-scale state transitions (LST).

“The FDA approval reinforces Myriad’s long-standing leadership in ovarian cancer diagnostics and underscores the clinical importance of comprehensive HRD testing,” said Brian Donnelly, Chief Commercial Officer, Myriad Genetics. “By enabling precise identification of patients who may benefit from PARP inhibitors, MyChoice CDx helps ensure that treatment decisions are guided by robust genomic insights.”

Nearly 50% of patients with advanced ovarian cancer have HRD positive (HRD+) tumors.¹ Identifying these patients is critical to ensuring appropriate use of PARP inhibitor therapy and improving personalized treatment decisions.^1-4

Zejula is a prescription medicine used for the maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer whose cancer is associated with HRD+ status defined by a deleterious or suspected deleterious BRCA mutation and/or genomic instability. Zejula is used after the cancer has responded (complete or partial response) to treatment with first-line platinum-based chemotherapy (Zejula indications referenced here apply to the US only). (For other indications, see “About Zejula” section below).

To learn more about the MyChoice CDx Test and how it can support treatment decisions for patients eligible for Zejula, please visit https://myriad.com/genetic-tests/mychoicecdx-tumor-test.

About the MyChoice CDx Test
The MyChoice ^® CDx Test is the only FDA-approved homologous recombination deficiency (HRD) test specifically mentioned in American Society of Clinical Oncology (ASCO) guidelines for selecting patients with ovarian cancer who may benefit from poly [ADP-ribose] polymerase (PARP) inhibitors.⁵ The MyChoice CDx Test determines HRD status by conducting a comprehensive assessment of BRCA1/2 genes and tumor genomic instability score (GIS) that includes loss of heterozygosity (LOH), telomeric allelic imbalance (TAI) and large-scale state transitions (LST). The MyChoice CDx Test can identify 34% more patients with HRD than other tumor tests that use %LOH alone.¹

About Zejula (niraparib)
Zejula is an oral, once-daily poly (ADP ribose) polymerase (PARP) inhibitor that works by preventing DNA repair in tumor cells, ultimately leading to their death. Zejula is indicated in the US for the maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in complete or partial response to first-line platinum-based chemotherapy and whose cancer is associated with homologous recombination deficiency (HRD)-positive status.

Zejula is also indicated for the maintenance treatment of adult patients with deleterious or suspected deleterious germline BRCA-mutated recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy and who have been selected based on a US FDA-approved companion diagnostic for Zejula (Zejula indications referenced here apply to the US only).

Please see the US Prescribing Information for Zejula.

About Myriad Genetics
Myriad Genetics is a leading molecular diagnostic and precision medicine company committed to advancing health and well-being for all. Myriad Genetics develops and commercializes molecular tests that help patients and providers uncover genetic insights. Myriad Genetics tests assess the risk of developing disease or disease progression and guide treatment decisions across medical specialties where molecular insights can significantly improve patient care, support earlier detection, enable more precise treatment and contribute to lowering healthcare costs. For more information, visit www.myriad.com.

Safe Harbor Statement
This press release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including statements that this FDA approval reinforces the company’s long-standing leadership in ovarian cancer diagnostics and underscores the clinical importance of comprehensive HRD testing, and that, by enabling precise identification of patients who may benefit from PARP inhibitors, MyChoice CDx helps ensure that treatment decisions are guided by robust genomic insights. These “forward-looking statements” are management’s expectations of future events as of the date hereof and are subject to known and unknown risks and uncertainties that could cause actual results, conditions, and events to differ materially and adversely from those anticipated. Such factors include those risks described in the company’s filings with the U.S. Securities and Exchange Commission, including the company’s Annual Report on Form 10-K filed on February 24, 2026, as well as any updates to those risk factors filed from time to time in the company’s Quarterly Reports on Form 10-Q or Current Reports on Form 8-K. Myriad is not under any obligation, and it expressly disclaims any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise except as required by law.

Konstantinopoulos PA, Ceccaldi R, Shapiro GI, D’Andrea AD. Homologous Recombination Deficiency: Exploiting the Fundamental Vulnerability of Ovarian Cancer. Cancer Discov. 2015;5(11):1137-1154.
Timms KM, Abkevich V, Hughes E, et al. Comparison of genomic instability test scores used for predicting PARP activity in ovarian cancer. J Clin Oncol. 2020;38(15_suppl):1586.
da Cunha Colombo Bonadio RR, Fogace RN, Miranda VC, Diz MDPE. Homologous recombination deficiency in ovarian cancer: a review of its epidemiology and management. Clinics (Sao Paulo). 2018;73(suppl 1):e450s.
Watkins JA, Irshad S, Grigoriadis A, Tutt AN. Genomic scars as biomarkers of homologous recombination deficiency and drug response in breast and ovarian cancers. Breast Cancer Res. 2014;16(3):211.
Tew WP, Lacchetti C, Birrer MJ, et al. PARP inhibitors in the management of ovarian cancer: ASCO guideline. J Clin Oncol. 2020;38(30):3468-3493

Investor Contact
Matt Scalo
(801) 584-3532
IR@myriad.com

Media Contact
Kate Schraml
(224) 875-4493
PR@myriad.com

FAQ

What did Myriad Genetics announce on March 17, 2026 about MyChoice CDx (MYGN)?

Myriad announced FDA approval of MyChoice CDx as the companion diagnostic for Zejula in the United States. According to the company, approval relied on final PRIMA trial data and designates MyChoice CDx as the only FDA-authorized CDx for Zejula.

How does the MyChoice CDx test determine HRD status for Zejula eligibility (MYGN)?

MyChoice CDx uses next-generation sequencing to assess BRCA1/2 and tumor genomic instability. According to the company, the GIS includes LOH, TAI and LST plus detection of large BRCA rearrangements to identify HRD-positive tumors.

What patient group is affected by the Myriad FDA approval for MyChoice CDx and Zejula (MYGN)?

The approval applies to adults with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are HRD-positive. According to the company, Zejula is for maintenance after response to first-line platinum-based chemotherapy in HRD+ patients.

Why is MyChoice CDx approval significant for Myriad Genetics shareholders (MYGN)?

FDA approval strengthens Myriad's leadership in ovarian cancer HRD testing and commercial positioning in the US. According to the company, being the only FDA-approved CDx for Zejula may support test adoption and clinical use in eligible patients.

Was the MyChoice CDx approval supported by clinical trial evidence (MYGN)?

Yes, the approval was based on final data from the PRIMA trial where MyChoice CDx determined HRD status and stratified patients. According to the company, PRIMA trial results formed the evidentiary basis for the FDA decision.

Myriad Genetics Receives FDA Approval of the MyChoice CDx Test as the Companion Diagnostic for Zejula (niraparib) for Patients with Ovarian Cancer