Registry data as of Aug 27, 2026

Jay Klarnet, MD

Medical Oncology Physician · Oxnard, CA

Jay Klarnet, MD is a medical oncology physician with a practice address in Oxnard, California, and NPI 1538258314, issued on Oct 12, 2006. Check the license (California G88453, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, loaded Aug 27, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordas of Aug 27, 2026
1538258314
Name
Jay Klarnet
Credential
MD
Primary taxonomy
Medical Oncology Physician 207RX0202X
License numbers
G88453 CA
Z185726 AZ
MD00021124 WA
Self-reported in NPPES; status is on the state search
Practice location
1700 N Rose Ave Ste 470, Oxnard, CA 93030
Phone
(805) 988-7080
Enumerated
Oct 12, 2006
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
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Also registered at 1700 N Rose Ave Ste 470

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Rachel Araujo, NPNurse Practitioner1508632316
  2. Amit Goyal, M.D.Neurological Surgery Physician1174813588
  3. Bradley Hiner, MDNeurology Physician1326099151
  4. Brittni Mack, PA-CSurgical Physician Assistant1063975753
  5. Brian MiremadiNeurology Physician1376078931
  6. Mani Nezhad, M.D.Neurology Physician1669716387

Verify Jay Klarnet in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license G88453
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

Statewide context: the Medical Board of California reported 374 disciplinary actions in FY 2022-23. California discipline data →

33% more Medicare Part D claims than the average medical oncology physician in 2024

934 Medicare Part D claims for 218 beneficiaries, against an average of 703 among the 4,230 providers of this specialty who prescribed in Part D. Brand-name drugs were 24% of claims. 38 claims were for opioids.

  1. Jay Klarnet934
  2. Specialty average703

Most prescribed

  1. Prednisone110 claims
  2. Anastrozole99 claims
  3. Eliquis45 claims
  4. Letrozole42 claims
  5. Dexamethasone41 claims
  6. Potassium Chloride34 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

The Medicare quality score for 2023: 0 of 100

The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.

  1. Qualityout of 100 · 30% of the final score0.0
  2. Costout of 100 · 30%
  3. Promoting interoperabilityout of 100 · 25%
  4. Improvement activities0 of 40 points · 15%0.0

Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).

Industry payments in 2024: $1,264.47

59 payments, mostly food and beverage; the largest payer was Janssen Biotech, Inc. The 3,343 providers of this specialty with any payment received $11,773.47 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Jay Klarnet$1,264.47
  2. Specialty average$11,773.47

Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.

Bills Medicare through 2 group practices

  1. Alaska Native Tribal Health ConsortiumAnchorage, AK
  2. Hrmc, LLCLake Havasu City, AZ

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov). Star ratings are CMS hospital ratings, not ratings of this provider.

Medical Oncology Physician providers in California

There are 447 medical oncology physician records in California.

Other medical oncology physician records in California

  1. Donald Abrams, MDSan Francisco, CA1679530018
  2. Ranjana Advani, MDStanford, CA1639225121
  3. Kambiz Afrasiabi, M.D.Anaheim, CA1578572368
  4. Mark Agulnik, MDLos Angeles, CA1164448734
  5. David Agus, M.D.Los Angeles, CA1356328249
  6. Weiyun Ai, MDSan Francisco, CA1649346842
  7. Shafqat Akhtar, MDRed Bluff, CA1700960788
  8. Luai Al Rabadi, M.D.San Francisco, CA1659637452
  9. Michael Alexander, MDSanta Cruz, CA1053321760
  10. Sandra AlgazeLos Angeles, CA1861886707

Common questions

What is Jay Klarnet, MD's NPI number?

Jay Klarnet, MD's National Provider Identifier (NPI) is 1538258314, issued on Oct 12, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Jay Klarnet, MD located?

The NPPES record lists a practice address at 1700 N Rose Ave Ste 470, Oxnard, CA, 93030. Phone: (805) 988-7080. Providers update this record themselves, so call before visiting.

How can I verify Jay Klarnet, MD's license?

NPPES lists California license number G88453, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Jay Klarnet, MD prescribe under Medicare Part D?

In 2024, Jay Klarnet, MD had 934 Medicare Part D claims for 218 beneficiaries; the average among medical oncology physician prescribers was 703. Part D covers Medicare prescriptions only.

What is Jay Klarnet, MD's Medicare quality score?

The 2023 MIPS final score is 0 of 100. The average among 454,083 clinicians with a measured score was 83.5.

Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments, the HHS-OIG exclusion list) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.