Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Isaac Andrew Klein, MD, PHD

Individual provider Internal Medicine Physician · NPI 1780022269

Dr. Isaac Andrew Klein, MD, PHD is an Internal Medicine Physician in Boston, Massachusetts. Licensed in Massachusetts. Registered with an NPI since 2013.

Licensed in
MA
In the registry since
2013
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.
PHD — Doctor of Philosophy
A research doctorate. In healthcare it usually sits alongside a clinical licence.

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Practice location Address checks out

75 Francis St
Boston, MA 02115-6110
Phone: (617) 732-5500
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 255783 (MA)

Record details

NPI number1780022269
Entity typeIndividual (Type 1)
GenderMale
Credentials MD , PHD
Sole proprietorNo
NPI enumeratedJune 6, 2013
Last updated in NPPESJune 6, 2013

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