G35.B0

🧠 ICD-10 CM G35.B0 — Primary Progressive Multiple Sclerosis, Unspecified

Billable Code Confirmed — FY2026 New Code

ICD-10-CM G35.B0 is a valid, billable ICD-10-CM code new for FY2026, effective October 1, 2025. It is the designated billable code for primary progressive multiple sclerosis when disease activity status (active vs. non-active) has not been documented in the medical record.

CRITICAL FY2026 Change — G35 and G35.B Are Not Billable

• ❌ G35 — Non-billable parent code as of October 1, 2025
• ❌ G35.B — Non-billable subcategory header — never submit alone
• ✅ G35.B0 — Billable code for PPMS when activity is unspecified

Submitting standalone G35 or G35.B after October 1, 2025 is invalid and will reject. The minimum valid code for PPMS without activity documentation is G35.B0.

G35.B0 Is a Query Opportunity — Activity Status Should Be Documented

ICD-10 CM G35.B0 should be assigned only after a good-faith effort to determine disease activity from the medical record or via CDI query. When PPMS activity status is documented, a more specific code is required — G35.B1 (active) or G35.B2 (non-active). G35.B0 is appropriate only when activity is genuinely undocumented after query. Activity status has direct implications for ocrelizumab authorization and DMT selection in PPMS.

Code Classification

ICD-10-CM Diagnosis Code — Fields for wRVU, assistant payable, and global period are not applicable. For associated inpatient procedure coding, see the ICD-10-PCS Crosswalk section below.

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🔍 Code Description

ICD-10-CM G35.B0 classifies primary progressive multiple sclerosis, unspecified — the subtype of MS defined by a gradual, continuous worsening of neurological function from the onset of symptoms, without early distinct relapses or remissions, in which the disease activity status (active vs. non-active) has not been documented in the medical record.

PPMS is clinically and biologically distinct from relapsing forms of MS. The disease course is driven primarily by progressive axonal loss and neurodegeneration rather than the discrete inflammatory demyelinating attacks that characterize relapsing-remitting MS. Patients with PPMS experience steadily accumulating disability — typically affecting spinal cord function with progressive gait impairment, lower extremity spasticity, and neurogenic bladder — from the time of first symptom onset.

The “unspecified” activity qualifier in G35.B0 reflects that the treating physician has documented primary progressive MS as the subtype but has not specified whether the disease is currently active (new MRI T1 gadolinium-enhancing lesion or new T2/FLAIR lesion, or clinical relapse activity) or non-active (stable MRI, no new lesion activity). The activity distinction is clinically meaningful because ocrelizumab (Ocrevus) — the only FDA-approved DMT for PPMS — is most strongly indicated in patients with active PPMS (G35.B1). A CDI query clarifying activity status upgrades G35.B0 to the more specific G35.B1 or G35.B2 and better reflects the clinical reality documented in the MRI and clinical notes.

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🌳 Code Tree / Hierarchy

│

├── G35.A — Relapsing-Remitting Multiple Sclerosis ✅ Billable

│

├── G35.B — Primary Progressive Multiple Sclerosis ❌ Non-billable header

│ ├── G35.B0 — Primary Progressive MS, Unspecified ◀ THIS CODE ✅ Billable

│ ├── G35.B1 — Active Primary Progressive MS ✅ Billable — see [G35.B1]

│ └── G35.B2 — Non-Active Primary Progressive MS ✅ Billable

│

├── G35.C — Secondary Progressive Multiple Sclerosis ❌ Non-billable header

│ ├── G35.C0 — Secondary Progressive MS, Unspecified ✅ Billable

│ ├── G35.C1 — Active Secondary Progressive MS ✅ Billable

│ └── G35.C2 — Non-Active Secondary Progressive MS ✅ Billable

│
└── G35.D — Multiple Sclerosis, Unspecified ✅ Billable — see [G35.D]

Upgrade Path — Activity Status Drives Specificity

G35.B0 is the intermediate code when subtype (PPMS) is confirmed but activity is undocumented. Once activity is clarified:

• Active PPMS (new Gd+ lesion, new T2 lesion, or clinical relapse) → G35.B1
• Non-active PPMS (stable MRI, no new lesion activity) → G35.B2

Reserve G35.B0 strictly for when activity status is genuinely undocumented after a query attempt.

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✅ Includes

The following clinical terms and documentation patterns map to G35.B0 when PPMS is confirmed but activity status is not specified:

• Primary progressive MS, activity not documented
• PPMS NOS
• Primary progressive multiple sclerosis without MRI activity specification
• PPMS in a patient transferred from a facility that used standalone G35 prior to FY2026, where the prior record reflects PPMS subtype but no activity documentation

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❌ Excludes

Excludes 1 — Cannot Be Coded Simultaneously with G35.B0

Code	Description	Note
G37.9	Demyelinating disease of CNS, unspecified	Mutually exclusive — once PPMS is confirmed, G37.9 is excluded entirely; do not code both
G35.B1	Active primary progressive MS	Mutually exclusive — if active PPMS is documented, assign G35.B1, not G35.B0
G35.B2	Non-active primary progressive MS	Mutually exclusive — if non-active PPMS is documented, assign G35.B2, not G35.B0

Excludes 1 — Only One G35.B Code at a Time

G35.B0, G35.B1, and G35.B2 are mutually exclusive with each other — only one may be assigned per encounter. G35.B0 is correct only when activity is genuinely unspecified; once activity is confirmed, the more specific code replaces it entirely. Do not assign G35.B0 alongside G35.B1 or G35.B2.

Excludes 2 — May Be Coded in Addition if Separately Present

Code	Description	Note
G36.0	Neuromyelitis optica (Devic disease)	Excludes 2 — distinct condition; may code alongside G35.B0 only if both are separately confirmed and documented

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📋 Clinical Overview

PPMS vs. RRMS vs. SPMS — Key Distinctions

PPMS represents approximately 10-15% of all MS diagnoses and has a fundamentally different clinical trajectory from relapsing forms. Unlike RRMS, there are no discrete attacks — the neurological decline is continuous, typically progressive from the outset, and more difficult to modify with available DMTs.

Feature	PPMS — G35.B0/B1/B2	RRMS — G35.A	SPMS — G35.C0/C1/C2
Onset pattern	Progressive from first symptom — no early relapses	Discrete relapses with recovery	Began as RRMS; transitioned to progressive course
Age at onset	Typically older (~45-50)	Typically younger (~20-40)	After RRMS course (variable)
Primary mechanism	Neurodegeneration / axonal loss from onset	Inflammatory demyelination	Mixed — neurodegeneration + residual inflammation
Spinal cord involvement	Predominant — progressive myelopathy	Variable	Variable
MRI appearance	Fewer brain lesions than RRMS; cord atrophy prominent	Periventricular lesions, Gd+ activity common during relapses	Cord atrophy + residual RRMS lesion burden
FDA-approved DMT	Ocrelizumab (Ocrevus) — for active PPMS	Multiple agents (interferons, natalizumab, siponimod, etc.)	Siponimod (Mayzent), ofatumumab (Kesimpta)
ICD-10 code family	G35.B0 / G35.B1 / G35.B2 — this family	G35.A	G35.C0 / G35.C1 / G35.C2

CDI Query Trigger — PPMS Activity Status

When the physician documents “primary progressive MS” or “PPMS” without specifying active or non-active status, a CDI query is warranted. Ask the neurologist: “The MRI from this admission — did it show new gadolinium-enhancing lesion(s) or new T2/FLAIR lesion(s) compared to the prior study? If so, is the PPMS currently considered active?” Activity documentation upgrades G35.B0 to G35.B1 or G35.B2 and better supports DMT authorization and payer documentation requirements.

Pathophysiology

Primary progressive MS is characterized by axonal degeneration and diffuse neuroinflammation rather than the focal demyelinating attacks that define relapsing MS. From the onset of symptoms, there is progressive loss of axons within the spinal cord and brain, driven by a smoldering innate immune response — activated microglia, meningeal lymphoid follicles, and chronic oxidative injury — that is less responsive to traditional anti-inflammatory DMTs than acute relapse-driven disease.

The spinal cord is the primary target in most PPMS cases, producing the classic presentation of progressive spastic paraparesis — gradually worsening leg stiffness, gait impairment, and balance dysfunction — along with neurogenic bladder and bowel dysfunction. Brain lesion burden in PPMS is typically lower than in RRMS on MRI, but cortical and deep gray matter involvement and brain volume loss (atrophy) correlate strongly with disability progression over time.

Clinical Presentation

Patients coded to G35.B0 present with the characteristic progressive myelopathic picture of PPMS:

• Progressive gait disturbance — the most common presenting complaint; leg stiffness, foot dragging, balance impairment worsening over months to years without discrete attack pattern
• Spastic paraparesis / paraplegia — lower extremity spasticity and weakness; G82.20 or G82.10 codeable when severity threshold met
• Neurogenic bladder — urinary urgency, frequency, retention; N31.9 should be coded when documented; very high prevalence in PPMS
• Upper extremity involvement — fine motor impairment, intention tremor in advanced cases
• Fatigue — severe, disproportionate; commonly underdocumented in inpatient notes
• Cognitive impairment — processing speed deficits, memory changes
• Pain — neuropathic pain and musculoskeletal pain from altered gait biomechanics
• Absent or rare relapses — the absence of discrete attack-recovery cycles is diagnostically important for PPMS classification

Documentation Requirements

For accurate assignment of G35.B0 — and to create the upgrade path to G35.B1 or G35.B2 — physician documentation should include:

1. MS subtype explicitly stated — “primary progressive MS” or “PPMS” must appear in physician documentation; not coder inference
2. Activity status — active vs. non-active; if specified, upgrade to G35.B1 or G35.B2 respectively
3. MRI findings — new Gd+ lesion or new T2 lesion = active; stable = non-active; physician must interpret and document
4. Disability level and functional status — documents severity of current episode and supports CC/MCC coding
5. Current DMT — ocrelizumab authorization requires active PPMS documentation; supports G35.B1 assignment when applicable

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💰 HCC Risk Adjustment (CMS-HCC v28)

Field	Detail
CMS-HCC Model Version	v28 (2024-2025 Implementation)
HCC Assignment	✅ HCC 198 — Multiple Sclerosis
HCC Category	HCC 198
RAF Coefficient	Verify current coefficient against CMS v28 publication
RxHCC Assignment	RxHCC v08: HCC 159

G35.B0 maps to CMS-HCC v28: HCC 198 (Multiple Sclerosis) and RxHCC v08: HCC 159. Verify the FY2026 G35.x subcategory code mapping against the current CMS crosswalk, as the new codes were added effective 10/1/2025 and mapping confirmation should be reviewed in your specific payer system.

PPMS Complications Carry Independent HCC Weight

At every G35.B0 encounter, review and ensure complete coding of all documented PPMS-related complications — PPMS patients carry a higher complication burden than RRMS patients due to advanced disability:

• Paraplegia / quadriplegia (G82.x) — HCC-mapped
• Hemiplegia / hemiparesis (G81.x) — HCC-mapped
• Neurogenic bladder (N31.x) — review HCC mapping; high prevalence in PPMS
• Aspiration pneumonia (J69.0) — MCC — very high DRG impact
• Pressure ulcers (L89.x stage 3/4) — MCC; common in non-ambulatory PPMS
• Malnutrition (E43, E44.x) — MCC/CC tier
• Sepsis (A41.x) — MCC

Do not leave risk-adjustable complications undercoded.

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🏥 MS-DRG Assignment

MDC 01 — Diseases and Disorders of the Nervous System

DRG	Title	Est. Relative Weight*
DRG 058	Multiple Sclerosis and Cerebellar Ataxia with MCC	~1.50-1.90
DRG 059	Multiple Sclerosis and Cerebellar Ataxia with CC	~1.00-1.30
DRG 060	Multiple Sclerosis and Cerebellar Ataxia without CC/MCC	~0.70-0.90

*Approximate. Verify against IPPS FY2026 Final Rule tables.

PPMS Patients Are Higher Acuity — CC/MCC Capture Is Critical

PPMS patients admitted inpatient are more likely than RRMS patients to present with advanced complication profiles — pressure injuries, neurogenic sepsis from UTI, aspiration pneumonia, and severe neurogenic bladder. J69.0 (aspiration pneumonia — MCC), L89.x stage 3/4 (pressure ulcer — MCC), and A41.x (sepsis — MCC) each move the encounter to DRG 058. Do not discharge-code a PPMS admission at DRG 060 without sweeping the full record for qualifying complications.

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🔗 Related ICD-10-CM Codes

The Complete FY2026 MS Code Family

Code	Description	Use When
G35.-	Multiple sclerosis ❌ NON-BILLABLE PARENT	Never submit after 10/1/2025
G35.A	Relapsing-remitting MS ✅	RRMS documented
G35.B0	Primary progressive MS, unspecified ✅	PPMS documented; activity not specified — THIS CODE
G35.B1	Active primary progressive MS ✅	PPMS with new MRI Gd+ or T2 lesion, or clinical relapse
G35.B2	Non-active primary progressive MS ✅	Stable PPMS; no new MRI activity documented
G35.C0	Secondary progressive MS, unspecified ✅	SPMS documented; activity not specified
G35.C1	Active secondary progressive MS ✅	SPMS with new MRI activity or superimposed relapse
G35.C2	Non-active secondary progressive MS ✅	Stable SPMS; no new activity documented
G35.D	Multiple sclerosis, unspecified ✅	Both subtype AND activity undocumented

Commonly Associated Additional Diagnosis Codes

Code	Description	Coding Relevance
G82.20	Paraplegia, unspecified	PPMS spinal cord involvement — code when lower extremity paralysis documented
G82.10	Paraparesis, unspecified	Incomplete spinal cord motor dysfunction in PPMS
N31.9	Neuromuscular dysfunction of bladder, unspecified	Neurogenic bladder — extremely common in PPMS; always query and code
M62.838	Other muscle spasm	PPMS-related spasm at non-back, non-calf site — code additionally when documented
R13.10	Dysphagia, unspecified	Brainstem or cerebellar PPMS involvement — may be MCC
J69.0	Aspiration pneumonia	MCC — complication of PPMS dysphagia; highest DRG impact
L89.x	Pressure ulcer (stage-specific)	Stage 3/4 = MCC; common in non-ambulatory PPMS patients
N39.0	Urinary tract infection	Common complication of neurogenic bladder in PPMS — CC tier
F06.30	Mood disorder due to known physiological condition	MS-related depression; code when documented
G35.B1	Active primary progressive MS	Upgrade target — assign when MRI activity or relapse is confirmed
G35.B2	Non-active primary progressive MS	Upgrade target — assign when stable PPMS without new MRI activity is confirmed

Differential Demyelinating Codes

Code	Description	Coding Relevance
G35.D	Multiple sclerosis, unspecified	Use when subtype AND activity are both undocumented — broader than G35.B0
G36.0	Neuromyelitis optica (Devic’s)	AQP4-IgG positive; distinct from PPMS — do not use G35.B0 for NMO
G37.3	Acute transverse myelitis in demyelinating disease	May coexist or be initial presentation before PPMS diagnosis

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🛠️ Commonly Associated CPT Codes

Outpatient and Physician Setting Context

The CPT codes below are associated with PPMS evaluation, infusion management, neurological monitoring, and spasticity/bladder management in outpatient and physician fee schedule settings. In the inpatient setting, ICD-10-PCS procedure codes govern procedural reporting.

CPT Code	Description	Clinical Application
99215	Office visit, established patient, high complexity	Complex PPMS management — DMT discussions, disability progression assessment
99214	Office visit, established patient, moderate complexity	Routine PPMS follow-up with medication and symptom management
96413	Chemotherapy administration, IV infusion, up to 1 hour	IV ocrelizumab (Ocrevus) infusion for active PPMS — first hour
96415	Chemotherapy administration, IV infusion, each additional hour	Additional hour(s) of ocrelizumab infusion
96360	IV infusion, hydration, initial 31-90 minutes	Pre/post-hydration with infusion therapy
97110	Therapeutic exercise	Physical therapy for PPMS gait impairment, strength maintenance
97140	Manual therapy techniques	Manual therapy for PPMS-related spasticity management
95930	Visual evoked potential (VEP) testing	Optic pathway assessment in PPMS surveillance
95925	Short-latency somatosensory evoked potential (SSEP)	Posterior column pathway integrity — commonly affected in PPMS
70553	MRI brain without and with contrast	PPMS surveillance — brain atrophy and new lesion detection
72157	MRI thoracic spine without and with contrast	Thoracic cord lesion assessment — primary PPMS target
51726	Complex cystometrogram	Urodynamic testing for PPMS neurogenic bladder evaluation

NCCI Bundling Considerations

NCCI PTP Edits — Verify Before Billing

• 96413 (ocrelizumab infusion) billed same DOS as E/M: Modifier -25 required on the E/M when separately documented beyond pre/post infusion assessment.
• 97110 (therapeutic exercise) and 97140 (manual therapy) same DOS: both are timed codes — confirm total timed minutes support billing both; NCCI PTP edits may apply by provider type and setting.
• 70553 (brain MRI) and 72157 (thoracic spine MRI) same DOS: typically separately payable; verify LCD/NCD multi-region MRI coverage requirements.

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🔬 ICD-10-PCS Crosswalk (Inpatient Procedures)

When G35.B0 is an inpatient diagnosis and a procedure is performed, the following ICD-10-PCS sections and root operations are relevant. Full PCS codes require completion of all seven characters — consult the PCS tables for the applicable fiscal year.

PCS Section	Body System	Root Operation	Clinical Application
0 (Medical & Surgical)	0 (Central Nervous System)	9 (Drainage)	Lumbar puncture (CSF analysis) — Body Part U (Spinal Canal), Approach 3 (Percutaneous), Qualifier X (Diagnostic)
3 (Administration)	3 (Peripheral Vein)	0 (Introduction)	IV infusion of therapeutic substance (ocrelizumab, methylprednisolone)
0 (Medical & Surgical)	0 (Central Nervous System)	H (Insertion)	Intrathecal baclofen pump implantation for PPMS spasticity management
3 (Administration)	0 (Central Nervous System)	0 (Introduction)	Intrathecal baclofen pump refill/dose adjustment
B (Imaging)	0 (Central Nervous System)	3 (MRI)	Brain and spinal cord MRI — structural lesion and atrophy assessment

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💊 Coding Scenarios and Examples

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Scenario 1 — PPMS, Activity Not Documented, Routine Infusion Visit (Outpatient)

Clinical Vignette: A 56-year-old male with known primary progressive MS presents for his scheduled ocrelizumab infusion. The neurologist’s note documents: “Primary progressive multiple sclerosis — scheduled Ocrevus infusion. No new symptoms since last visit. Continue current plan.” No MRI performed at this visit. No activity status documented.

CPT Codes (Outpatient Infusion):

• 96413 — IV infusion, first hour (ocrelizumab)
• 96415 — IV infusion, each additional hour
• 99214--25 — E/M if separately documented beyond infusion pre/post assessment

ICD-10-CM:

• G35.B0 — Primary progressive MS, unspecified (PPMS documented; activity not specified at this encounter — G35.B0 is correct)

No MRI at This Visit — Activity Cannot Be Inferred

Without MRI results reviewed at this encounter, the coder cannot assign G35.B1 or G35.B2. G35.B0 correctly captures PPMS with unspecified activity. If the prior surveillance MRI is referenced in this note and activity is commented on, that opens the door for a CDI query to upgrade to B1 or B2.

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Scenario 2 — PPMS, Admitted for Progressive Paraparesis, Activity Unknown (Inpatient)

Clinical Vignette: A 61-year-old female with PPMS is admitted after her family notes worsening leg weakness and inability to transfer independently over the past 3 weeks. MRI spine performed — results show cord atrophy without clearly new T2 lesions compared to prior study; no Gd+ enhancement. Neurology documents: “Primary progressive MS — progressive disability. Awaiting full MRI comparison report.” Activity status not formally documented at time of discharge coding.

Principal Diagnosis:

• G35.B0 — Primary progressive MS, unspecified (PPMS documented; MRI comparison pending; activity status not confirmed at discharge)

Additional Diagnoses:

• G82.20 — Paraplegia, unspecified (documented lower extremity paralysis severity threshold met)
• N31.9 — Neuromuscular dysfunction of bladder (neurogenic bladder documented in nursing notes and physician assessment)

MS-DRG Assignment:

• DRG 059 — with CC (if G82.20 or N31.9 qualifies as CC — confirm CC tier)

CDI Query Opportunity — MRI Comparison Is Pending

Once the MRI comparison report is finalized, the neurologist should document whether new lesion activity is present. If the attending addends the discharge summary to confirm non-active PPMS, upgrade G35.B0 to G35.B2. If new T2 lesion activity is confirmed, upgrade to G35.B1. A late query before bill drop is appropriate and preferred over defaulting to G35.B0 when the answer is obtainable.

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Scenario 3 — PPMS, Aspiration Pneumonia Complication (Inpatient MCC)

Clinical Vignette: A 68-year-old male with advanced PPMS is admitted with aspiration pneumonia. He is non-ambulatory with known dysphagia from cerebellar involvement. Physician documents “primary progressive MS with aspiration pneumonia secondary to neurogenic dysphagia.” Activity status not documented.

Principal Diagnosis:

• G35.B0 — Primary progressive MS, unspecified (PPMS driving admission; activity not documented)

Additional Diagnoses:

• J69.0 — Aspiration pneumonia (MCC — elevates DRG to 058)
• R13.10 — Dysphagia, unspecified (neurogenic dysphagia from PPMS cerebellar involvement — code additionally)

MS-DRG Assignment:

• DRG 058 — Multiple Sclerosis and Cerebellar Ataxia with MCC (J69.0 is MCC — maximum DRG weight)

Aspiration Pneumonia Is MCC — Never Miss This

J69.0 moves the encounter to DRG 058. In non-ambulatory PPMS patients with documented dysphagia, aspiration pneumonia is a predictable, clinically significant complication. Complete documentation and coding of J69.0 alongside G35.B0 is clinically accurate and the difference between the lowest and highest MS DRG weight.

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⚠️ Coding Pitfalls and Tips

	Pitfall or Tip
❌	Do not submit G35- or G35.B alone — both are non-billable after 10/1/2025; minimum valid code for unspecified PPMS activity is G35.B0
❌	Do not assign G35.B0 when activity is documented — if active → G35.B1; if non-active → G35.B2; G35.B0 is strictly for undocumented activity
❌	Do not assign G35.B0 alongside G35.B1 or G35.B2 — mutually exclusive; only one G35.B code per encounter
❌	Do not infer activity from MRI imaging alone — gadolinium enhancement or new T2 lesion suggests active disease but physician documentation is required for G35.B1 assignment
❌	Do not confuse PPMS with SPMS — PPMS is progressive from onset without prior RRMS history; SPMS evolves from a prior relapsing course; the distinction is physician-documented and not coder-inferred
✅	Query for activity status at every PPMS encounter — ask the neurologist whether the current MRI shows new Gd+ or T2 lesion activity; one documentation sentence upgrades B0 → B1 or B2
✅	G35.B0 carries CMS-HCC v28: HCC 198 / RxHCC v08: HCC 159 — confirm mapping on current CMS crosswalk
✅	Capture all PPMS complications — neurogenic bladder (N31.x), paraplegia (G82.x), aspiration pneumonia (J69.0), pressure ulcers (L89.x) drive DRG tier and RAF
✅	J69.0 is MCC — moves PPMS admission to DRG 058; never miss in non-ambulatory patients with documented dysphagia
✅	Neurogenic bladder is near-universal in PPMS — if not coded, it is a CDI and compliance gap; query and code N31.x when documented

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📚 Sources

1. CMS/NCHS. ICD-10-CM Official Guidelines for Coding and Reporting, FY2026. Tabular List — G35.B0; G35.B subcategory structure; Excludes 1/Excludes 2 notations at G35 category level.

2. CMS. FY2026 Addendum B — ICD-10-CM New, Revised, and Deleted Diagnosis Codes. G35B0 added; G35 deleted as billable code.

3. CMS. 2025-2026 Medicare Advantage Risk Adjustment — CMS-HCC Model v28 ICD-10-CM Mappings. G35 family: CMS-HCC v28 HCC 198 (Multiple Sclerosis); RxHCC v08 HCC 159.

4. CMS. IPPS Final Rule FY2026 — MS-DRG Definitions Manual v43. MDC 01 logic tables — DRG 058/059/060 Multiple Sclerosis and Cerebellar Ataxia.

5. CMS. ICD-10-PCS Reference Manual FY2026. Section 0 (Medical & Surgical), Body System 0 (CNS); Section 3 (Administration).

6. Lublin FD, et al. Defining the clinical course of multiple sclerosis: The 2013 revisions. Neurology. 2014;83(3):278-286. (Clinical basis for PPMS classification and activity distinction reflected in FY2026 codes.)

7. Montalban X, et al. Ocrelizumab versus placebo in primary progressive multiple sclerosis. N Engl J Med. 2017;376(3):209-220. (Clinical basis for active PPMS DMT authorization — G35.B1 relevance.)

8. AMA. CPT Professional Edition 2026. Neurology and Neuromuscular Procedures (95800-96020); Evaluation and Management guidelines; Infusion/Injection subsection.

9. CMS. NCCI Policy Manual for Medicare Services, current version. Neurology chapter and general correct coding principles.