Plus Therapeutics Receives Medicare Enrollment Approval for CNSide Diagnostic

Rhea-AI Summary

Plus Therapeutics (Nasdaq: PSTV) announced that subsidiary CNSide Diagnostics is enrolled in Medicare and received a Provider Transaction Access Number (PTAN), establishing the lab as Medicare‑enrolled for the CNSide® CSF Assay Platform including the tumor cell enumeration (TCE) test. Claims will be reimbursed if deemed reasonable and necessary by the local Medicare Administrative Contractor.

The company cited a pathway to ~35 million Medicare Advantage beneficiaries, existing ~81 million commercial covered lives, and a target of 150 million+ covered lives in 2026. A new CPT code 0640U is effective for billing July 1, 2026, with pricing via crosswalk or gapfill.

AI-generated analysis. Not financial advice.

Positive

• Medicare enrollment secured with a PTAN for CNSide Diagnostics
• Pathway to ~35 million Medicare Advantage beneficiaries
• Existing ~81 million commercial covered lives already in place
• New CPT code 0640U effective for billing July 1, 2026
• 2026 target of 150 million+ covered lives

Negative

• Reimbursement contingent on local MAC coverage determinations
• CLFS pricing for CPT 0640U subject to crosswalk or gapfill uncertainty
• Coverage expansion depends on negotiations with Medicare Advantage payers
• Medicaid enrollment still requires state-by-state credentialing

News Market Reaction – PSTV

-0.83%

3 alerts

-0.83% News Effect

-7.0% Trough Tracked

-$345K Valuation Impact

$41.17M Market Cap

1.63K Volume

On the day this news was published, PSTV declined 0.83%, reflecting a mild negative market reaction. Argus tracked a trough of -7.0% from its starting point during tracking. Our momentum scanner triggered 3 alerts that day, indicating moderate trading interest and price volatility. This price movement removed approximately $345K from the company's valuation, bringing the market cap to $41.17M at that time.

Data tracked by StockTitan Argus on the day of publication.

Key Figures

Medicare Advantage reach: ~35 million Commercial covered lives: ~81 million Covered lives goal: 150 million+ +2 more

5 metrics

Medicare Advantage reach ~35 million Potential pathway to Medicare Advantage beneficiaries via future coverage decisions

Commercial covered lives ~81 million Existing commercial coverage base cited for CNSide platform

Covered lives goal 150 million+ 2026 target for total covered lives across payers

CPT code 0640U New CPT code for CNSide CSF TCE test under CLFS

CLFS billing start July 1, 2026 Effective date for billing under CPT code 0640U

Market Reality Check

Price: $6.12 Vol: Volume 175,460 is below t...

low vol

$6.12 Last Close

Volume Volume 175,460 is below the 20-day average of 374,505, indicating muted pre-news trading interest. low

Technical Shares at $6.00 are trading below the $11.17 200-day MA and about 74.39% under the 52-week high.

Peers on Argus

PSTV was down 3.54% pre-news while momentum data show peer RADX up 5.64999990165...

1 Up

PSTV was down 3.54% pre-news while momentum data show peer RADX up 5.649999901652336%. With no peers moving down in the scanner, the setup looks stock-specific rather than a sector-wide move.

Historical Context

5 past events · Latest: Apr 28 (Positive)

Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Apr 28	Payer coverage expansion	Positive	-0.7%	Blue Shield of California added reimbursement, lifting covered lives to ~81M.
Apr 23	Manufacturing agreement	Positive	-4.5%	SpectronRx added as second GMP site to support late-stage REYOBIQ supply.
Apr 22	Inducement equity grants	Positive	-4.5%	Equity awards granted to new Chief Development Officer under Nasdaq rules.
Apr 21	Nasdaq compliance regained	Positive	-2.2%	Company confirmed back in compliance with Nasdaq minimum bid requirement.
Apr 15	Key HEOR hire	Positive	+4.0%	VP of Value Strategy & HEOR appointed to support CNSide and REYOBIQ.

Pattern Detected

Across the last five generally positive news events, PSTV declined the next day in 4 cases and rose in 1, showing a tendency for weak or contrarian reactions to favorable headlines.

Recent Company History

Over the past month, Plus Therapeutics has focused on strengthening capital markets compliance, leadership, and commercialization. On April 2, 2026, a reverse split supported bid-price compliance, followed by confirmation of Nasdaq compliance on April 21, 2026. The company added HEOR and development leadership and expanded CNSide coverage, including Blue Shield of California. Despite these seemingly constructive developments, four of the last five news days saw negative next-day price reactions, so today’s Medicare enrollment milestone fits into a backdrop of cautious trading responses.

Market Pulse Summary

This announcement highlights a meaningful commercialization step as CNSide Diagnostics gains Medicar...

Analysis

This announcement highlights a meaningful commercialization step as CNSide Diagnostics gains Medicare enrollment and a PTAN, enabling billing for the CNSide CSF TCE test under a new CPT code 0640U from July 1, 2026. The company already cites ~81 million commercial covered lives and targets 150 million+ by 2026. Investors may watch how MAC coverage determinations, Medicare Advantage contracts, and real-world adoption evolve against this expanded reimbursement framework.

Key Terms

medicare advantage, provider transaction access number (ptan), medicare administrative contractor (mac), clinical laboratory fee schedule (clfs), +4 more

8 terms

medicare advantage financial

"creates a pathway to ~35 million Medicare Advantage beneficiaries"

Medicare Advantage is a type of health insurance plan offered by private companies that covers services traditionally provided by government-run Medicare. Think of it as a bundled package that combines hospital, doctor, and other medical care into one plan, often with added benefits. For investors, it matters because the popularity and profitability of these plans can influence healthcare companies and the broader health insurance industry.

provider transaction access number (ptan) regulatory

"received a Provider Transaction Access Number (PTAN) from the Centers"

A Provider Transaction Access Number (PTAN) is a unique identifier issued by Medicare administrators that health providers use when submitting claims and checking payment status. Think of it as the account number a doctor or clinic uses specifically for Medicare billing; it links services provided to the correct payer records. For investors, PTANs matter because they affect how and when healthcare organizations receive government reimbursements, impacting cash flow and revenue reporting.

medicare administrative contractor (mac) regulatory

"by the Medicare Administrative Contractor (MAC) with jurisdiction"

A Medicare Administrative Contractor (MAC) is a private company hired by the government to process Medicare claims, decide how services and products are billed, and implement local payment rules. Think of a MAC as a regional billing office and referee that determines whether and how much Medicare will pay for a treatment or device. Investors care because MAC decisions and payment timing directly affect healthcare providers’ and medical suppliers’ revenue, cash flow, and market forecasts.

clinical laboratory fee schedule (clfs) regulatory

"CMS pricing determinations under the Clinical Laboratory Fee Schedule (CLFS)"

The Clinical Laboratory Fee Schedule (CLFS) is a government-set list of payment rates for clinical lab tests that determines how much public health programs will reimburse laboratories and diagnostic companies. Think of it as a large customer’s approved price list — changes to the CLFS directly affect a lab’s revenue, profit margins and cash flow, so investors watch updates closely as they can alter future earnings and competitiveness in the diagnostics market.

cpt code regulatory

"payment rate for the new CPT code 0640U (CNSide CSF TCE Test)"

A CPT code is a standardized numeric label used by healthcare providers and insurers to identify medical procedures, tests, and services for billing and reimbursement. Think of it as a SKU or price tag for each clinical service: which code is used and how it’s reimbursed directly affects a provider’s revenue and a medical product’s market adoption, so investors watch codes and payment rules to estimate financial impact.

circulating tumor dna medical

"detects and characterizes tumor cells and circulating tumor DNA in"

Fragments of DNA shed by cancer cells into the bloodstream that act like tiny fingerprints of a tumor; they can be detected with a blood test rather than a biopsy. Investors care because circulating tumor DNA (ctDNA) enables faster, lower-cost ways to detect disease, track treatment response, identify emerging resistance and enroll patients in trials—factors that can materially affect the commercial prospects of diagnostics and therapeutics.

leptomeningeal metastases medical

"for patients with leptomeningeal metastases — a devastating complication"

Leptomeningeal metastases occur when cancer cells spread to the thin layers of tissue covering the brain and spinal cord, similar to how weeds can invade the surface layer of soil. This condition often indicates advanced disease and can lead to serious neurological problems. For investors, the presence of such metastases may signal challenges in treatment options and can impact the outlook for related healthcare companies or research developments.

laboratory-developed tests medical

"commercializes proprietary laboratory-developed tests, such as CNSide®"

Laboratory-developed tests are medical tests that a single clinical laboratory designs, builds and runs internally rather than buying from outside manufacturers. Think of them as an in-house recipe a lab creates to detect a disease or measure a biomarker; they matter to investors because they can drive revenue, offer faster product development and carry distinct regulatory and reimbursement risks that affect a healthcare company's financial outlook.

AI-generated analysis. Not financial advice.

Enables billing under traditional Medicare and creates a pathway to ~35 million Medicare Advantage beneficiaries through future payer coverage decisions

HOUSTON, May 07, 2026 (GLOBE NEWSWIRE) -- Plus Therapeutics, Inc. (Nasdaq: PSTV) (“Plus” or the “Company”), a healthcare company developing and commercializing precision diagnostics and radiopharmaceuticals for central nervous system (CNS) cancers, today announced that its wholly owned subsidiary, CNSide Diagnostics, LLC (“CNSide Diagnostics”), has successfully enrolled in the Medicare program and received a Provider Transaction Access Number (PTAN) from the Centers for Medicare & Medicaid Services (CMS).

This key milestone establishes CNSide Diagnostics as a Medicare-enrolled clinical laboratory, enabling the submission of claims for its CNSide^® Cerebrospinal Fluid (CSF) Assay Platform, including the tumor cell enumeration (TCE) test. Claims will be reimbursed when determined to be reasonable and necessary by the Medicare Administrative Contractor (MAC) with jurisdiction over the laboratory.

“Medicare enrollment represents a critical step in our commercialization strategy,” said Russ Havranek, EVP Corporate and Commercial Strategy. “It enables access to approximately half of the U.S. Medicare population through Traditional Medicare, subject to coverage determinations, while establishing a clear pathway to expand into Medicare Advantage populations over time. Combined with our existing ~81 million commercial covered lives, this milestone strengthens our pathway to broader patient access, adoption, and revenue growth.”

Strategic and Commercial Impact

• Expanded Billing of Traditional Medicare: Enables billing for testing furnished to Medicare Fee-For-Service beneficiaries, subject to coverage determination by our local Medicare Administrative Contractor (MAC)
• Pathway to Medicare Advantage: Positions CNSide Diagnostics to pursue coverage with Medicare Advantage plans, including those administered by United Healthcare, Humana, Highmark, Blue Shield of California, and other national and regional payers
• Accelerates Coverage and Pricing Efforts: Enables active engagement with MACs to pursue local coverage determinations (LCDs) and supports CMS pricing determinations under the Clinical Laboratory Fee Schedule (CLFS)
• Medicaid Momentum: Provides essential credentialing for state-by-state Medicaid enrollment

Next Steps: Reimbursement Momentum

With Medicare enrollment secured, CNSide Diagnostics is focused on the following near-term milestones:

• Medicare Coverage Pathway — Engagement with MACs to secure formal coverage determinations
• CLFS Pricing — Establishment of a payment rate for the new CPT code 0640U (CNSide CSF TCE Test), effective for billing July 1, 2026, via crosswalk or gapfill methodology
• Further Commercial Expansion — Continued execution of national and regional payer contracts toward the 2026 goal of 150 million+ covered lives
  
  

Positioning CNSide Diagnostics for Scaled Adoption

The CNSide^® CSF Assay Platform is a novel diagnostic tool that detects and characterizes tumor cells and circulating tumor DNA in cerebrospinal fluid. It enables earlier and more accurate diagnosis, disease monitoring, and treatment decision-making for patients with leptomeningeal metastases — a devastating complication of CNS cancers where conventional methods like MRI and cytology frequently fall short.

With Medicare enrollment now complete, CNSide Diagnostics is executing a focused commercialization strategy to drive broad clinical adoption:

• Payer Coverage Expansion: Building on the current 81 million commercial covered lives to further broaden access through additional national and regional payer contracts
• Clinical Utility & Health Economics: Generating robust real-world data to demonstrate improved patient outcomes and cost-effectiveness
• Key Account Engagement: Deepening relationships with leading academic medical centers and community oncology networks
• Reimbursement Optimization: Refining coding, billing, and collections processes to maximize efficiency and revenue capture

About CNSide Diagnostics, LLC

CNSide Diagnostics, LLC is a wholly owned subsidiary of Plus Therapeutics, Inc. based in Houston, Texas that develops and commercializes proprietary laboratory-developed tests, such as CNSide^®, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. The CNSide^® CSF Assay Platform enables quantitative analysis of the cerebrospinal fluid that informs and improves the management of patients with leptomeningeal metastases.

About Plus Therapeutics

Headquartered in Houston, Texas, Plus Therapeutics, Inc. is a clinical-stage pharmaceutical company developing targeted radiotherapeutics for difficult-to-treat cancers of the central nervous system with the potential to enhance clinical outcomes. Combining image-guided local beta radiation and targeted drug delivery approaches, the Company is advancing a pipeline of product candidates with lead programs in leptomeningeal metastases (LM) and recurrent glioblastoma (GBM). The Company has built a supply chain through strategic partnerships that enable the development, manufacturing, and future potential commercialization of its products.

Forward-Looking Statements

This press release contains statements that may be deemed “forward-looking statements” within the meaning of U.S. securities laws, including statements regarding clinical trials, expected operations and upcoming developments. All statements in this press release other than statements of historical fact are forward-looking statements. These forward-looking statements may be identified by future verbs, as well as terms such as “expect,” “potential,” “anticipating,” “planning” and similar expressions or the negatives thereof. Such statements are based upon certain assumptions and assessments made by management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate. These statements include, without limitation, statements regarding the potential market for the CNSide^® CSF Assay, the timing as to when the CNSide^® CSF Assay will be commercially launched and expanded, revenue and corporate profitability expectations including support reimbursements and payments for the CNSide^® CSF Assay, the development, utility and acceptance of the CNSide^® CSF Assay, and expectations as to the Company’s future performance, including development and commercialization of the Company’s product candidates.

Investor Contact
CORE IR
investor@plustherapeutics.com

FAQ

What does PSTV’s Medicare enrollment for CNSide mean for billing?

It permits CNSide Diagnostics to submit claims to Traditional Medicare for the CNSide CSF tests. According to the company, claims will be reimbursed when the local Medicare Administrative Contractor finds them reasonable and necessary.

How many Medicare Advantage beneficiaries could CNSide reach after PSTV enrollment?

Enrollment creates a pathway to about 35 million Medicare Advantage beneficiaries. According to the company, further access depends on individual Medicare Advantage plan coverage decisions and contracting.

When can providers bill CPT code 0640U for the CNSide CSF TCE test (PSTV)?

The new CPT code 0640U is effective for billing on July 1, 2026. According to the company, CLFS pricing will be established via crosswalk or gapfill methodologies before reimbursement rates are finalized.

Does PSTV’s Medicare enrollment guarantee immediate reimbursement for CNSide tests?

No, immediate reimbursement is not guaranteed; it is subject to local MAC coverage determination. According to the company, claims will be reimbursed only when a Medicare Administrative Contractor deems them reasonable and necessary.

How does PSTV plan to expand payer coverage after Medicare enrollment?

PSTV plans to pursue local coverage determinations, negotiate Medicare Advantage contracts, and expand commercial payer agreements. According to the company, efforts include CLFS pricing engagement and continued national and regional payer contracting toward 150 million+ covered lives.