Lanadelumab & Garadacimab (Takhzyro & Andembry)

Lanadelumab and garadacimab are two real, FDA-approved monoclonal antibodies that prevent hereditary angioedema attacks by blocking the same bradykinin-generating cascade this site's icatibant, ecallantide and C1-inhibitor pages already cover — just at two further points upstream. Lanadelumab (2018) was the first antibody built specifically for HAE prevention; garadacimab (approved worldwide from January 2025, and by the FDA in June 2025) blocks a step earlier still, at the cascade's actual trigger, and reached five other regulators before the FDA. Both rest on real, published, placebo-controlled Phase 3 trials with strong, statistically clear results.

Two more ways to block the same cascade

Hereditary angioedema (HAE) attacks are driven by excess bradykinin, generated through a cascade this site's icatibant, ecallantide, conestat alfa and Berinert & Cinryze pages already describe: activated Factor XII triggers plasma kallikrein, which cleaves a precursor into bradykinin, which then acts on the B2 receptor to cause swelling. C1-esterase inhibitor normally restrains the cascade far upstream, which is why replacing it (conestat alfa, Berinert, Cinryze) works; ecallantide blocks plasma kallikrein directly; icatibant blocks the B2 receptor at the very end of the line. Lanadelumab and garadacimab are two newer monoclonal antibodies that block the same cascade at two further points, built specifically for long-term prevention rather than treating an attack already underway.

Lanadelumab: the first antibody built for HAE prevention

Lanadelumab is a fully human monoclonal antibody that selectively inhibits active plasma kallikrein — the same target ecallantide blocks, but as a long-acting antibody rather than a single-dose recombinant protein. It began as SHP643 (originally DX-2930) at Dyax Corp, the same company that developed ecallantide; Shire acquired Dyax in January 2016 for roughly $5.9 billion, largely on the strength of this program, and Shire itself was acquired by Takeda in January 2019 — so lanadelumab, like ecallantide, is now a Takeda product. The FDA approved it (as Takhzyro) on 23 August 2018 for HAE prophylaxis in patients 12 and older, based on the Phase 3 HELP trial (Banerji A, Riedl MA, Bernstein JA, et al., JAMA 2018;320(20):2108-2121, PMID 30480729, DOI: 10.1001/jama.2018.16773): 125 patients randomized to placebo or one of three lanadelumab dosing regimens over 26 weeks. Placebo patients averaged 1.97 attacks per month; the 300mg-every-2-weeks group averaged roughly 0.26, an 87% reduction, with the other two active-dose arms also significantly better than placebo. On 3 February 2023 the FDA expanded the approval down to children as young as 2, and the label allows patients who stay attack-free for 6 months to step down from dosing every 2 weeks to every 4.

Garadacimab: one step further upstream, and approved everywhere else first

Garadacimab (formerly CSL312) is a fully human monoclonal antibody developed in-house by CSL Behring that binds and inhibits activated Factor XIIa — the enzyme that actually starts the contact-activation cascade, a step upstream of the plasma kallikrein that lanadelumab and ecallantide block. Its Phase 3 VANGUARD trial (Craig T, et al., Lancet 2023;401(10382):1079-1090, PMID 36868261, DOI: 10.1016/S0140-6736(23)00350-1) randomized 64 adult and adolescent patients roughly 3:2 to garadacimab (a 400mg loading dose, then 200mg once monthly, self-injected) or placebo over 6 months. The least-squares-mean attack rate reduction vs. placebo was 89.2%, the median reduction was over 99%, and 61.5% of garadacimab patients had zero attacks for the entire 6-month treatment period, versus none of the placebo group.

What this adds to the site's HAE cluster

Between them, this site now covers five distinct HAE drug mechanisms: replacing the missing C1-inhibitor itself (conestat alfa, Berinert, Cinryze); blocking plasma kallikrein with a single-dose recombinant protein for an attack in progress (ecallantide) or a long-acting antibody for ongoing prevention (lanadelumab); blocking the bradykinin B2 receptor for on-demand treatment (icatibant); and now blocking Factor XIIa itself, the cascade's actual trigger, for monthly prevention (garadacimab). Both lanadelumab and garadacimab remain in active use for HAE prophylaxis, with no boxed warnings beyond standard injection-site-reaction and hypersensitivity monitoring common to the whole antibody class.