Arash Rezazadeh Kalebasty, M.D.

Hematology/Oncology (CMS) · Orange, CA

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At a glance

101 The City Dr S Bldg 23, Orange, CA 92868-3201

NPPES record updated Apr 14, 2023. Public records can lag behind changes at a practice.

Before you call: a quick checklist
  • Are you accepting new patients?
  • Do you accept my specific insurance plan?
  • Do you provide the service I need at this address?
  • Do I need a referral, and what is the earliest appointment?

Insurance participation and appointment availability are not established by these public records.

Medicare & insurance

Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.

How to check your coverage

Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.

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Practice location

101 The City Dr S Bldg 23
Orange, CA 92868-3201
REPORTED BACKGROUND

Education & affiliations

Medical / professional school
Not reported in this file
Graduation year
1989
CMS specialties
Hematology/Oncology

CMS reports telehealth services for this clinician. Confirm current services and availability with the practice.

Practice groups

Reported hospital affiliations

Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.

Source: CMS National Downloadable File · Published Oct 15, 2026.

Source: CMS Facility Affiliation Data · Published Oct 15, 2026.

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PUBLISHED MEDICARE ACTIVITY

Procedures in the public data

Reported activity can help you ask more informed questions about a practice’s services.

No displayed procedure-category record in this release. This does not mean the clinician performs no procedures.

CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology

Source: CMS Utilization Data · Published Oct 15, 2026.

Find providers with a similar service mix

Compare 2024 published Medicare activity in the same reported specialty, here or in another city.

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PAYMENT TRANSPARENCY

Industry-reported general payments

$69,976.71General payments · 2025
63Reported transactions
9Reporting companies

Includes reported transfers of value, such as meals, travel, or consulting. Payments do not establish improper conduct or quality of care. Research funding and ownership values are excluded from this total.

See payment purposes and reporting companies

Reported purposes

PurposeAmount
Services other than consulting$39,365.75
Medical education speaking or faculty$16,005.00
Consulting fee$7,222.50
Travel and lodging$5,872.05
Food and beverage$1,492.39
Entertainment$19.02

Reporting companies

CompanyAmount
EXELIXIS INC.$20,385.62
BAYER HEALTHCARE PHARMACEUTICALS INC.$19,013.68
MERCK SHARP & DOHME LLC$13,182.62
JANSSEN BIOTECH, INC.$12,921.37
NOVARTIS PHARMACEUTICALS CORPORATION$2,100.00
EMD SERONO, INC.$1,380.00
PFIZER INC.$749.50
AVEO PHARMACEUTICALS, INC.$190.29
Other reporting companies$53.63
View official Open Payments profile ↗

Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.

Professional details: NPI, taxonomy & registry record
NPI1205974755
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Registry details

Primary taxonomy
Hematology/Oncology (CMS)
Taxonomy code
207RH0003X
Enumeration date
Feb 4, 2007
Record updated
Apr 14, 2023
More registry details
Provider type
Individual · Type 1
Reported credentials
M.D.

Reported taxonomies and licenses

Specialty details in registry

207RH0003X

License reported: 40927 KY

Specialty details in registry

207RH0003X · Primary

License reported: C167307 CA

License numbers and credentials are reported to NPPES; HCPList does not independently verify them.

Practice location

101 The City Dr S Bldg 23
Orange, CA 92868-3201
Phone
(714) 456-8000
Mailing address
200 S MANCHESTER AVE STE 300

ORANGE, CA 928683219
Source: NPPES Source through Oct 18, 2026An NPI does not verify licensure or credentials.

Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.

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