What is the Crohn’s & Ulcerative Colitis (IBD) biologic cost calculator?
This calculator estimates the annual drug cost and the real out-of-pocket burden of biologics, an integrin inhibitor, and JAK inhibitors used to treat inflammatory bowel disease (IBD) — Crohn’s disease and ulcerative colitis.
You pick a drug — Remicade/Remsima (infliximab), Humira (adalimumab), Entyvio (vedolizumab), Stelara (ustekinumab), Tremfya (guselkumab), Simponi (golimumab), Rinvoq (upadacitinib), or Xeljanz (tofacitinib) — and it applies coverage, the copay special case, the annual out-of-pocket ceiling, biosimilar savings, private indemnity insurance, and the medical-expense tax credit, step by step.
Biologics cost several million to tens of millions of KRW a year, but for the same drug the real burden varies enormously with (1) whether it meets the reimbursement criteria, (2) special-case registration, and (3) biosimilar choice.
Crucially, Crohn’s disease (ICD code K50) and ulcerative colitis (K51) are registered rare/intractable special-case conditions, so the covered copay is 10% — not the 5% used for cancer.
Korea-based estimate. This calculator is built on Korean National Health Insurance rules for 2026 (rare/intractable-disease special-case registration for Crohn’s K50 and ulcerative colitis K51 at a 10% copay, the annual out-of-pocket ceiling, private indemnity insurance, and the medical-expense tax credit). Drug prices are benefit-ceiling-based public estimates that change with formulation, weight-based IV dosing, induction dosing, and risk-sharing agreements. It is an educational estimate, not medical advice, and does not replace diagnosis, treatment decisions, a hospital quote, or an insurer/benefit decision.
IBD biologics and JAK inhibitors
IBD drugs target a specific inflammatory signal or block immune-cell trafficking into the gut.
Options differ by disease (Crohn’s vs ulcerative colitis), and some drugs are reimbursed only for ulcerative colitis.
TNF-α inhibitors (first-line IBD biologics)
- • Remicade/Remsima (infliximab): weight-based (5 mg/kg) IV infusion, induction at weeks 0/2/6 then every 8 weeks; biosimilars (Remsima, Renflexis) available
- • Humira (adalimumab): every-2-week subcutaneous self-injection, induction 160→80 mg; many biosimilars (Adalloce, Yuflyma)
- • Simponi (golimumab): ulcerative colitis only, monthly subcutaneous injection (induction 200→100 mg)
Integrin, IL-12/23, and IL-23 inhibitors
- • Entyvio (vedolizumab): a gut-selective α4β7 integrin inhibitor with little systemic immunosuppression; 300 mg IV every 8 weeks (subcutaneous maintenance option)
- • Stelara (ustekinumab): IL-12/23 inhibitor, one weight-based IV induction then 90 mg subcutaneous every 8 weeks; a biosimilar (Steqeyma) has appeared
- • Tremfya (guselkumab): IL-23 inhibitor, reimbursed for both Crohn’s and ulcerative colitis from June 2026 (Korea’s first IL-23 for IBD)
JAK inhibitors (oral pills)
- • Rinvoq (upadacitinib): both Crohn’s and ulcerative colitis, induction 45 mg then maintenance 15–30 mg once daily
- • Xeljanz (tofacitinib): ulcerative colitis only, induction 10 mg then maintenance 5 mg twice daily
Mirikizumab (Omvoh), an IL-23 inhibitor used abroad, is not yet reimbursed for IBD in Korea as of 2026 and is therefore fully non-covered.
IV drugs are given at the hospital while subcutaneous/oral drugs are taken at home, so the route changes both the copay and how private insurance processes the claim.
When is it covered? (reimbursement criteria)
Because biologics are expensive, they are not covered from the outset — only moderate-to-severe patients who did not respond adequately to prior therapy qualify.
If you are treated without meeting the criteria, you pay 100% of the drug cost as non-covered.
Criteria by disease (summary)
- • Crohn’s disease: moderate-to-severe activity (e.g., CDAI ≥ 220) with inadequate response, intolerance, or contraindication to 2+ of corticosteroids and immunomodulators (azathioprine, 6-MP). Children (6–17) after failing steroids/immunomodulators/exclusive enteral nutrition
- • Ulcerative colitis: moderate-to-severe activity (e.g., Mayo score) with inadequate response, intolerance, or contraindication to steroids and immunomodulators
- • Second-line drugs: some drugs, such as vedolizumab (Entyvio), are reimbursed after failure, intolerance, or contraindication to a TNF-α inhibitor
Even after starting on coverage, response is usually reassessed around weeks 8–14 to decide on continuation, and treatment is stopped if there is no response.
The exact rules follow the Ministry of Health and Welfare notice on detailed reimbursement standards for drugs, and require a physician’s judgment.
The special case is 10%, not 5%
Many people confuse this with the cancer special case (5% copay), but the special case for Crohn’s disease and ulcerative colitis is a rare/intractable disease, so the copay is 10%.
Even so, insurance covers 90% of the covered drug cost, which cuts the burden sharply.
Rare/intractable-disease special case — key points
- • Crohn’s (K50) and ulcerative colitis (K51): registered rare/intractable special-case conditions, covered copay 10%
- • Special mark (V-code): once registered in the hospital system, the covered copay is automatically applied at 10%
- • Registration period: valid for 5 years, with re-registration before expiry to keep the benefit
- • Difference from cancer: cancer and severe-burn special cases are 5%, but Crohn’s and ulcerative colitis, as rare/intractable diseases, are 10%
The basis is Annex 2, item 3 of the Enforcement Decree of the National Health Insurance Act (rare/intractable diseases at 10% of total covered cost) and the Ministry of Health and Welfare notice “Standards for Special Cases of Copayment” (list of rare/intractable special-case conditions).
The special case applies only to covered items — the 10% does not apply to non-covered drug cost.
Biosimilar vs originator
A biosimilar is a drug proven equivalent in efficacy and safety to the originator biologic, and its lower price reduces your out-of-pocket cost.
Originator prices are also often cut administratively due to biosimilar competition.
Key IBD biosimilars
- • Infliximab (Remicade): Remsima, Renflexis, etc. (Korean biosimilars lead the global market)
- • Adalimumab (Humira): Adalloce, Yuflyma, Hadlima, etc.
- • Ustekinumab (Stelara): Steqeyma, etc. (lower price than the originator)
If you have already hit the annual out-of-pocket ceiling, the originator and the biosimilar can end up with the same annual burden.
This calculator compares both cases and shows the savings.
IV vs subcutaneous/oral
IBD biologics differ in copay form and private-insurance processing by route of administration.
Choosing the matching care setting reflects the copay rate accurately.
- • IV at the hospital: infliximab, vedolizumab, etc. are infused in the outpatient infusion room; ordinary benefit self-pay 30–60% by hospital level plus an injection fee. The higher the body weight, the higher the mg/kg drug cost
- • Subcutaneous self-injection: Humira, Simponi, and Stelara maintenance are self-injected at home, usually pharmacy-dispensed at 30% benefit self-pay
- • Oral pills: JAK inhibitors such as Rinvoq and Xeljanz are pharmacy-dispensed at 30%
With special-case registration, the covered copay is a uniform 10% regardless of route.
IV is processed as outpatient or inpatient, while subcutaneous/oral drug cost is processed as outpatient medical expense by private insurance.
Out-of-pocket ceiling and medical-expense tax credit
Biologics are often taken near-continuously for years, so the annual out-of-pocket ceiling and the medical-expense tax credit greatly lower the real burden.
Both are based on the covered copay and the burden remaining after private-insurance reimbursement.
Two programs — key points
- • Annual out-of-pocket ceiling: if annual covered copay exceeds the income-tier cap (about KRW 900,000–8,430,000 in 2026), the excess is refunded, and it applies again every year during long-term treatment
- • Medical-expense tax credit: 15% of medical spending above 3% of gross salary, excluding private-insurance reimbursement
- • Serious-illness limit: registered special-case patients (Crohn’s and ulcerative colitis) have no KRW 7,000,000 cap on the medical-expense tax credit (Income Tax Act Article 59-4(2))
- • Without registration, the ordinary KRW 7,000,000 annual cap applies
How to use this calculator
Step 1: Disease and drug
Pick Crohn’s disease or ulcerative colitis to filter the drugs reimbursed for that disease, then choose the drug, originator/biosimilar, coverage status, and treatment period.
Step 2: Copay conditions
Set special-case registration, care setting (IV outpatient / subcutaneous pharmacy / inpatient), income tier, and the out-of-pocket ceiling.
Both Crohn’s and ulcerative colitis are rare/intractable special-case conditions.
Step 3: Insurance and tax credit
Enter your private indemnity insurance generation and gross annual salary to reflect reimbursement and the medical-expense tax credit.
Step 4: Review results
See annual copay, biosimilar / special-case / covered-vs-non-covered comparisons, the ceiling refund, private-insurance reimbursement, the tax credit, and the final real burden at a glance.
Frequently asked questions (FAQ)
Q. Is the IBD special-case copay 5% like cancer?
A. No. Cancer is a serious-illness special case at 5%, but Crohn’s disease and ulcerative colitis are rare/intractable special-case conditions, so the copay is 10%.
Insurance still covers 90% of the covered drug cost, and you can get an additional refund through the out-of-pocket ceiling.
Q. How is Entyvio (vedolizumab) different?
A. Vedolizumab is a gut-selective α4β7 integrin inhibitor with little systemic immunosuppression, which is why its safety profile is emphasized for IBD.
In Korea it is usually reimbursed after a TNF-α inhibitor has failed, so confirm your treatment history with your physician.
Q. Does switching to a biosimilar reduce efficacy?
A. A biosimilar is proven equivalent in efficacy and safety to the originator through MFDS approval.
Infliximab (Remsima) and adalimumab (Adalloce) are widely used in IBD and cost less, so discuss switching with your physician.
Q. How much is it if it isn’t covered?
A. If you are treated fully non-covered because you don’t meet the criteria, you pay 100% of the drug cost.
That runs several million to tens of millions of KRW a year with no special-case or ceiling benefit, so confirm eligibility first.
Q. Can private insurance reimburse the injection cost?
A. Therapeutic biologic injections and drug costs are eligible for private indemnity insurance.
It reimburses the covered copay and non-covered drug cost at your generation’s coinsurance rate, subject to per-visit and annual limits — check your policy.
Important notes
- Reference estimate: prices vary with actual transaction price, weight (mg/kg for IV), dose, risk-sharing agreements, and induction dosing; this calculator uses 2026 public drug prices.
- Coverage is individual: whether the criteria (steroid/immunomodulator failure, disease activity) are met depends on the patient, so confirm with your physician and HIRA.
- Long-term therapy: biologics are often taken long term because stopping risks relapse, and the ceiling refund must be claimed year by year.
- Rules change: special-case criteria, drug prices, reimbursement rules, and the out-of-pocket ceiling can change yearly — check the latest notice.
Estimate your IBD biologic cost now
Enter the drug, disease, special case, and income tier to see the annual real burden at a glance.
Compare biosimilar savings and the out-of-pocket ceiling refund in one place.