Vimizim (elosulfase alfa) — HCPCS J1322
CareCost Estimate · Billing Cheat Sheet
BioMarin Pharmaceutical
5 mg / 5 mL single-dose vial
IV infusion ~3.5–4.5 hr, weekly
Reviewed: May 2, 2026
ASP: Q2 2026
BOXED WARNING — ANAPHYLAXIS: Severe hypersensitivity reactions including anaphylaxis observed
during/after infusion. Healthcare-setting admin with epinephrine + resuscitation equipment immediately available.
Premedication (antihistamines ± antipyretics, 30–60 min pre) required. Post-infusion observation. Add
corticosteroid for prior reactors.
Dose
2 mg/kg q wk
e.g. 60 units / 30 kg
Modifier
JW
Most claims (5 mg vials)
Admin CPT
96365
+ 96366 × 3 (3.5–4.5 hr)
Medicare ASP+6%
$311.946
/mg · $18,716.76 / 60 mg
Codes & NDC
| HCPCS | J1322 — "Elosulfase alfa, injection" (permanent) |
|---|
| NDC | 68135-0020-01 (11) / 68135-020-01 (10) — N4 qualifier |
|---|
| Vial | 5 mg / 5 mL (1 mg/mL) single-dose |
|---|
| Indication | MPS IVA / Morquio A syndrome — only FDA-approved ERT |
|---|
| Benefit | Medical (provider buy-and-bill or specialty pharmacy white-bag) |
|---|
Dosing & vial math
- 2 mg/kg IV once weekly — lifelong; adults + pediatric ≥5 yr
- Infusion: ~3.5–4.5 hr (initial slower rate, ramp up)
- Vials = ceiling((kg × 2) / 5)
- Most weights = partial-vial waste →
JW required
- 52 doses/year typical; year-1 = 52 × (kg × 2) units
| Wt | Dose | Vials | Waste |
|---|
| 15 kg | 30 mg | 6 | 0 (JZ) |
| 30 kg | 60 mg | 12 | 0 (JZ) |
| 32 kg | 64 mg | 13 | 1 (JW) |
| 52 kg | 104 mg | 21 | 1 (JW) |
| 70 kg | 140 mg | 28 | 0 (JZ) |
Premedication checklist
- ☐ Antihistamine 30–60 min pre (PO or IV)
- ☐ Antipyretic 30–60 min pre (per protocol)
- ☐ Corticosteroid added if prior reaction history
- ☐ Epinephrine + resuscitation equipment chairside, in date
- ☐ Patient/caregiver counseled on anaphylaxis signs
- ☐ Vitals q 15–30 min during infusion documented
- ☐ Post-infusion observation completed before discharge
Administration & modifiers
| Code | When |
|---|
96365 | Therapeutic IV, first hour (primary) |
96366 | Each additional hour — bill ~3 units (4 hr infusion) |
96413 | Not appropriate — Vimizim is enzyme replacement, not chemo |
JW | Wasted units (separate line) — most claims |
JZ | No-waste claim (weights divisible by 2.5 kg) |
Document infusion start/stop times. Long infusions get audited — bill 96366 increments per actual full additional hours.
ICD-10 — Morquio family
| Code | For |
|---|
E76.219 | Morquio syndrome unspecified (default primary) |
E76.210 | Morquio A — preferred when GALNS deficiency confirmed |
E76.211 | NO — Morquio B not covered by Vimizim |
| Add organ-involvement codes: I35.x (valve), J96.x / G47.33 (resp/OSA), M40.x / M41.x (kypho/scoli), H18.4x (corneal), H90.x (hearing) |
Diagnosis confirmation required: GALNS enzyme assay + GALNS gene mutation analysis + specialist letter. ICD-10 alone insufficient.
MPS class comparison — ERTs by subtype
| Disease | Brand (HCPCS) | Generic |
|---|
| MPS I | Aldurazyme (J1931) | laronidase |
| MPS II (Hunter) | Elaprase (J1743) | idursulfase |
| MPS III | No FDA ERT |
| MPS IVA | Vimizim (J1322) | elosulfase alfa |
| MPS IVB | No FDA ERT |
| MPS VI | Naglazyme (J1458) | galsulfase |
| MPS VII | Mepsevii (J3397) | vestronidase |
Not interchangeable. Each MPS subtype has its own enzyme; ERTs are NOT cross-substitutable.
Payer requirements (May 2026)
| Payer | PA | Documentation |
|---|
| UnitedHealthcare | Yes | GALNS assay + gene + specialist + baseline echo/PFT/MRI |
| Aetna | Yes | Confirmed Dx + specialist + 6MWD/PFT/cardiac monitoring |
| BCBS plans | Yes | Aligned with FDA label + AAP MPS guidelines |
| Cigna / Evernorth | Yes | Confirmed Dx + specialist; reauth at 6–12 mo |
No step therapy. Vimizim is the only ERT for MPS IVA — no class alternative.
Medicare reimbursement (Q2 2026)
| Field | Value |
|---|
| ASP + 6% | $311.946 / mg (4/1 – 6/30/2026) |
| 30 kg patient (60 mg) | $18,716.76/dose |
| 70 kg patient (140 mg) | $43,672.44/dose |
| Annual 30 kg (52 doses) | ~$973,272 |
| Annual 70 kg (52 doses) | ~$2,270,966 |
Site of care
| Setting | POS | Notes |
|---|
| Hospital outpatient | 22/19 | Common early; HOPD steered after stabilization |
| Ambulatory infusion suite | 49 | Preferred long-term |
| Physician office (metabolic) | 11 | If anaphylaxis-equipped |
| Patient home | 12 | Specialty home-infusion vendor; payer often requires prior in-clinic tolerance |
Patient assistance — BioMarin RareConnections
- Phone: 1-866-906-6100
- Benefits investigation, PA assistance, appeal support
- Commercial copay: co-pay assistance program (excludes Medicare/Medicaid/federal)
- PAP: free product for uninsured/underinsured
- Foundation referrals: PAN, HealthWell, NORD (verify open MPS funds)
- Travel + infusion logistics support for families
- Web: vimizim.com · biomarin.com/patient-support