Long-term reductions in HAE attacks1

Pivotal study: The safety and efficacy of DAWNZERA were evaluated in the randomized, placebo-controlled OASIS-HAE trial. At Week 242:

  • Q4W (n=45) demonstrated a significant reduction in the mean monthly attack rate vs placebo (n=22), (LSM 0.44 vs 2.26; primary endpoint, P<0.001)
  • Q8W (n=23) reduction in LSM attack rate vs placebo was 1.02 vs 2.26 (P=0.004)

Open-label extension:

94% reduction. 94% reduction.

after 1 year of treatment across both Q4W and Q8W dosing arms1†

Reductions in mean monthly HAE attack rate from baseline (investigator-confirmed)1*
Clinical data chart showing reductions in mean monthly HAE attack rate from baseline Clinical data chart showing reductions in mean monthly HAE attack rate from baseline
  • Placebo
  • DAWNZERA Q4W
  • DAWNZERA Q8W
  • 1st dose of DAWNZERA
  • 2nd dose of DAWNZERA
  • Placebo patients start DAWNZERA

*This pre-specified analysis of the ongoing OASISplus study reports results for only patients who completed the open-label extension through Week 52 as of a January 27, 2025 data cut, and not all patients enrolled in the OASIS-HAE trial.1

†Secondary endpoint.

Reductions in mean monthly HAE attack rate from baseline (investigator-confirmed)1*

Clinical data chart showing reductions in mean monthly HAE attack rate from baseline
  • Placebo
  • DAWNZERA Q4W
  • DAWNZERA Q8W
  • 1st dose of DAWNZERA
  • 2nd dose of DAWNZERA
  • Placebo patients start DAWNZERA

*This pre-specified analysis of the ongoing OASISplus study reports results for only patients who completed the open-label extension through Week 52 as of a January 27, 2025 data cut, and not all patients enrolled in the OASIS-HAE trial.1

†Secondary endpoint.

Pivotal study: Attack-free results2,3*

DAWNZERA Q4W (n=45):

53% vs 9%

with placebo (n=22; P=0.003)

Week 4 to Week 24

DAWNZERA Q8W (n=23):

35% vs 9%

with placebo (n=22; P=NS)

Week 4 to Week 24

NS=not significant; Q4W=every 4 weeks; Q8W=every 8 weeks.

*Secondary endpoint.

HAE=hereditary angioedema; LSM=least-squares mean; Q4W=every 4 weeks; Q8W=every 8 weeks.

DAWNZERA Q8W: HAE attack reductions by attack severity2,3*

Pivotal study

DAWNZERA Q8W (n=23)

41%

fewer moderate-to-severe HAE attacks

LSM change vs placebo

from Week 4 to Week 24 (P=NR) 

DAWNZERA Q8W (n=23)

67%

fewer attacks requiring acute therapy

LSM change vs placebo

from Week 4 to Week 24 (P=0.004)

 Open-label extension (1 year)1

DAWNZERA Q8W (n=14)

91%

fewer moderate-to-severe HAE attacks

Mean change from placebo-controlled 

trial baseline

from Week 4 to Week 52 

DAWNZERA Q8W (n=14)

97%

fewer attacks requiring acute therapy

Mean change from placebo-controlled 

trial baseline

from Week 4 to Week 52

HAE=hereditary angioedema; LSM=least-squares mean; NR=not reported; Q8W=every 8 weeks. 

*Secondary endpoint.

HAE attack reductions by disease severity†

Pivotal study3

LSM change vs placebo from Week 4 to Week 24 
(Q4W, n=45), (P<0.001 for both)

severity-reduction severity-reduction

Open-label extension (1 year)1

Mean change from placebo-controlled trial baseline from Week 4 to Week 52 (Q4W, n=69)

severity-reduction hae attack reduction data img

HAE=hereditary angioedema; LSM=least-squares mean; Q4W=every 4 weeks; Q8W=every 8 weeks. 

†Secondary endpoint.

Study design: Pivotal study (OASIS-HAE) and open-label extension study (OASISplus)

Study design diagram showing the OASIS-HAE placebo-controlled trial and OASISplus open-label extension rollover and switch cohorts. Study design diagram showing the OASIS-HAE placebo-controlled trial and OASISplus open-label extension rollover and switch cohorts.

OASIS-HAE: Phase 3, randomized, double-blind, placebo-controlled 24-week trial of patients aged ≥12 years with HAE type 1 or 2 (N=90)2,3

  • At baseline, 69% of patients had >2 monthly attacks2
  • Enrolled patients had to have at least 2 investigator-confirmed attacks during the 8-week run-in period2

OASISplus: Ongoing, open-label, long-term safety (primary endpoint) and efficacy (secondary endpoint) study of patients with HAE type 1 or 2 (N=147)1,5

  • Open-label extension cohort: After 24 weeks, patients in OASIS-HAE were able to continue into the OASISplus open-label extension study†
  • Open-label switch cohort: An independent cohort of patients enrolled and had to be on a stable dose of prophylactic therapy for ≥12 weeks. Patients started taking DAWNZERA every 4 weeks on study Day 1, following the 14-day switch protocol

92% of eligible patients opted to continue in the open-label extension study1†

C1-INH=C1-inhibitor; HAE=hereditary angioedema; Q4W=every 4 weeks; Q8W=every 8 weeks.

*Pooled placebo every 4 and 8 weeks.2

†83 of 90 eligible patients rolled over into the open-label extension study.1

Reductions in ER visits‡

Pivotal study3

95% FEWER ER VISITS

due to HAE attacks from Week 0 to Week 24

(Q4W, LSM change vs placebo)

Open-label extension4

No ER visits

due to HAE attacks from Week 0 to Week 52
 (Q4W)

ER=emergency room; HAE=hereditary angioedema; LSM=least-squares mean; Q4W=every 4 weeks.

‡Exploratory endpoint.

See other areas to explore for DAWNZERA:

View switch data View patient-reported outcomes

IMPORTANT SAFETY INFORMATION & INDICATION

CONTRAINDICATIONS

DAWNZERA is contraindicated in patients with a history of serious hypersensitivity reactions, including anaphylaxis, to donidalorsen or any of the excipients in DAWNZERA.

WARNINGS AND PRECAUTIONS

Hypersensitivity Reactions

Hypersensitivity reactions, including anaphylaxis, have been reported in patients treated with DAWNZERA. If signs and symptoms of serious hypersensitivity reactions occur, discontinue DAWNZERA and institute appropriate therapy.

ADVERSE REACTIONS

Most common adverse reactions (incidence ≥ 5%) are injection site reactions, upper respiratory tract infection, urinary tract infection, and abdominal discomfort.

INDICATION

DAWNZERA (donidalorsen) is indicated for prophylaxis to prevent attacks of hereditary angioedema (HAE) in adult and pediatric patients 12 years of age and older.

Please see full Prescribing Information for DAWNZERA.

References: 1. Lumry WR, Tachdjian R, Craig T, et al. Donidalorsen for long-term prophylaxis of hereditary angioedema attacks: results from the OASISplus open-label extension cohort at year 1.  J Asthma Allergy. 2026;19:592079. doi:10.2147/JAA.S592079 2. DAWNZERA. Prescribing information. Ionis Pharmaceuticals. 3. Riedl MA, Tachdjian R, Lumry WR, et al. Efficacy and safety of donidalorsen for hereditary angioedema. N Engl J Med. 2024;391(1):21-31. doi:10.1056/NEJMoa2402478 4. Data on file. Ionis Pharmaceuticals. 5. Riedl MA, Bernstein JA, Jacobs JS, et al. Switching long-term prophylaxis to donidalorsen for hereditary angioedema: 1-year OASISplus results. Allergy. 2026;1-10. doi:10.1111/all.70294 6. Riedl MA, Bernstein JA, Jacobs JS, et al. Donidalorsen treatment of hereditary angioedema in patients previously on long-term prophylaxis. J Allergy Clin Immunol Pract. 2025;13(9):2381-2389.e3. doi:10.1016/j.jaip.2025.06.018 7. Riedl MA, Tachdjian R, Lumry WR, et al. Efficacy and safety of donidalorsen for hereditary angioedema. Supplementary appendix. N Engl J Med. 2024;391(1):21-31. doi:10.1056/NEJMoa2402478