Transthyretin Amyloid Cardiomyopathy (ATTR-CM)Phase 3LTSAFE-ALXNNCT07789483
An Open-Label Study to Evaluate the Long-Term Safety and Efficacy of ALXN2220 in Adults With Transthyretin Amyloid Cardiomyopathy
A Phase 3 study testing ALXN2220 in people with Transthyretin Amyloid Cardiomyopathy (ATTR-CM), run by Alexion Pharmaceuticals, Inc. at 195 sites in 27 countries.
Trial summary
The purpose of Study ALXN2220-ATTRCM-302 is to evaluate the long-term safety, tolerability and efficacy of ALXN2220 in adult participants with ATTR-CM treated with ALXN2220 in addition to SoC who have completed Study ALXN2220-ATTRCM-301. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Transthyretin Amyloid Cardiomyopathy (ATTR-CM)
- What is being tested?
- ALXN2220
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,180 participants
- Where
- 195 sitesin 27 countries
- Study dates
- 23 Nov 2027to 11 Jul 2030
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Type of Participant: Participants who have completed the Blinded Treatment Period (including the PC visit) of Study 301.
- Sex and Contraceptive/Barrier Requirements: Male and/or female (according to their reproductive organs and functions assigned by chromosomal complement).
- Informed Consent: Participant, or legally authorized representative where relevant and allowed by law, is willing and able to comply with all study requirements and to provide signed informed consent.
Who cannot join
- Participants who permanently discontinued study intervention in Study 301
- Participants who withdrew full consent during Study 301.
- Medical Conditions: Suspected or known intolerance/allergy to proteins or any components of ALXN2220. Has had a heart transplant or permanent CMAD implantation. Has any new or worsening of existing medical or psychological condition or risk factor that in the opinion of the Investigator or Sponsor might jeopardize participant's safety or compliance with the protocol, or pose any additional risk for the participant, or confound the assessment of the participant or outcome of the study.
- Prior/Concurrent/Future Clinical Study Experience: Current or future participation in another investigational clinical study or intake of investigational drug within 30 calendar days or 5 half-lives of the study intervention, whichever is longer, before signing the ICF, except for study intervention used in Study 301.
Trial locations and contacts
195 sites in 27 countries. Contact the study team or a site near you to ask about taking part.
195 sites in 27 countries
United States35 sites
Research Site
Atlanta, Georgia, 30309
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Atlanta, Georgia, 30322
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Aurora, Colorado, 80045
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Boston, Massachusetts, 02115
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Boston, Massachusetts, 02118
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Chapel Hill, North Carolina, 27599
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Charleston, South Carolina, 29425
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Cleveland, Ohio, 44195
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Columbus, Ohio, 43210
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Danville, Pennsylvania, 17822
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Durham, North Carolina, 27705
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Falls Church, Virginia, 22042
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Fort Worth, Texas, 76104
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Greenville, South Carolina, 29605
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Houston, Texas, 77030
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Indianapolis, Indiana, 46202
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Irvine, California, 92614
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Jacksonville, Florida, 32224
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Kansas City, Missouri, 64111
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La Jolla, California, 92037
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Madison, Wisconsin, 53705
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Memphis, Tennessee, 38120
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New York, New York, 10016
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New York, New York, 10032
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Palo Alto, California, 94304
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Philadelphia, Pennsylvania, 19104
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Portland, Oregon, 97239
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Richmond, Virginia, 23298
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Salt Lake City, Utah, 84132
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San Francisco, California, 94143
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Seattle, Washington, 98195
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St Louis, Missouri, 63110
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Stony Brook, New York, 11794
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Washington D.C., District of Columbia, 20010
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Weston, Florida, 33331
China16 sites
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Beijing, Beijing Municipality, 100037
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Beijing, Beijing Municipality, 100191
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Beijing, 100730
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Changsha, Hunan, 430033
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Chongqing, Chongqing Municipality, 400042
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Guangzhou, Guangdong, 510080
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Guiyang, Guizhou, 550044
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Hangzhou, Zhejiang, 310003
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Hangzhou, Zhejiang, 310009
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Harbin, Heilongjiang, 150080
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Jinan, Shangdong, 250021
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Nanjing, Jiangsu, 210029
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Shanghai, Shanghai Municipality, 201114
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Tianjin, 300457
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Wuhan, Hubei, 430030
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Xi'an, Shaanxi, 710061
Germany13 sites
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Berlin, Deutschalnd, 10117
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Cologne, North Rhine-Westphalia, 50937
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Essen, 45147
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Gie En, 35392
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Hamburg, 22767
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Hanover, Lower Saxony, 30625
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Heidelberg, 69120
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Homburg, Saarland, 66421
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Kiel, Schleswig-Holstein, 24105
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Leipzig, Saxony, 04103
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M Nchen, 81377
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Münster, Munster, 48149
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W Rzburg, 97078
Italy13 sites
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Bologna, Bologna, 40138
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Ferrara, 44124
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Florence, Florence, 50134
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Forlì, Emilia-Romagna, 47121
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Messina, Messina, 98124
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Milan, 20122
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Naples, Napoli, 80131
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Padova, Padova, 35128
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Pavia, 27100
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Pisa, PI, 56124
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Rome, Lazio, 00189
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Torino, TO, 10154
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Trieste, TS, 34128
Spain13 sites
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A Coruña, Galicia, 15009
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Barcelona, Catalonia, 8035
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El Palmar, Murcia, 30120
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Jaén, Andalusia, 23007
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L'Hospitalet de Llobregat, Catalonia, 08907
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Madrid, Madrid, 28027
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Majadahonda, Madrid, 28222
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Málaga, Andalusia, 29010
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Palma de Mallorca, Balearic Islands, 07198
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Pamplona, Navarre, 31008
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Salamanca, Castille and León, 37007
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Santiago de Compostela-Coru A, Galicia, 15706
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Valencia, Comunidad Valencia, 46010
France12 sites
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Bron, 69677
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Chambray-lès-Tours, 37170
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Créteil, 94010
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Marseille, 13005
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Montpellier, 34295
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Paris, 75018
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Paris, 75651
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Pessac, 33604
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Poitiers, 86021
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Rennes, 35033
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Saint-Herblain, 44093
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Toulouse, 31059
Brazil10 sites
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Campinas, São Paulo, 13083
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Fortaleza, Ceará, 60430-375
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Porto Alegre, Rio Grande do Sul, 90560-030
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Ribeirão Preto, São Paulo, 14026-020
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Ribeirão Preto, São Paulo, 14051-140
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Rio de Janeiro, Rio de Janeiro, 20551-030
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Rio de Janeiro, Rio de Janeiro, 22270-005
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São Paulo, São Paulo, 04012-909
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São Paulo, São Paulo, 05403-000
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São Paulo, São Paulo, 05652-900
Japan8 sites
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Bunkyo-ku, Tokyo, 113-8431
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Kumamoto, Kumamoto, 860-8556
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Kurume-shi, Fukuoka, 830-0011
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Kyoto, Kyoto, 602-8566
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Matsumoto-shi, Nagano, 390-8621
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Sapporo, Hokkaido, 060-8543
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Shinjuku-ku, Tokyo, 160-8582
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Suita-shi, Osaka, 564-8565
Australia7 sites
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Bedford Park, South Australia, 5042
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Box Hill, Victoria, 3128
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Brisbane, Queensland, 4102
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Darlinghurst, New South Wales, 2010
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Joondalup, Western Australia, 6027
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Melbourne, Victoria, 3004
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Westmead, New South Wales, 2145
Canada7 sites
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Calgary, Alberta, T2N 1N4
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Chicoutimi, Quebec, G7H 5H6
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London, Ontario, N6A 5A5
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Montr Al, Quebec, H1T 1C8
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Montr Al, Quebec, H2X 1R9
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Rimouski, Quebec, G5L 5T1
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Winnipeg, Manitoba, R2H 2A6
South Korea6 sites
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Busan, 49241
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Seoul, Seoul, 03080
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Seoul, Seoul, 03722
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Seoul, Seoul, 06351
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Seoul, Seoul, 06591
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Seoul, Seoul, 5505
United Kingdom6 sites
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Birmingham, Edgbaston, B16 8QQ
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Cardiff, CF15 9SS
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Glasgow, Scotland, G20 0SP
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London, GREATER LONDON, NW3 2QG
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London, London, SE1 1YR
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Manchester, M15 6SE
Argentina5 sites
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Buenos Aires, Buenos Aires, 1425
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CABA, Buenos Aires, C1025ABI
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Ciudad de Buenos Aires, Buenos Aires F.D., C1181ACH
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Ciudad de Buenos Aires, C1428
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Córdoba, Córdoba Province, X5016KEH
Austria5 sites
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Graz, 8036
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Innsbruck, 6020
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Vienna, 1090
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Vienna, 1160
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Wels, 4600
Switzerland5 sites
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Basel, 4031
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Bern, 3010
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Lucerne, 6000
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Sankt Gallen, 9007
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Zurich, 8091
Israel4 sites
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Beer Yaakov, 70300
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Haifa, 31096
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Jerusalem, 91120
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Rehovot, 76100
Netherlands4 sites
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Groningen, 9713 GZ
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Maastricht, 6229 HX
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Rotterdam, 3015 GD
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Utrecht, 3584 CX
Sweden4 sites
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Gothenburg, 413 45
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Lund, Skåne County, 22242
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Skellefte, Skelleftea, 93186
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Stockholm, 171 64
Taiwan4 sites
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Taichung, Taichung, 404
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Taichung, Taichung, 40705
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Taipei, Taipei, 10002
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Taipei, Taiwan, 11217
Turkey (Türkiye)4 sites
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Dinar, 03400
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Eskişehir, 26480
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Istanbul, 34303
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Mersin, Mersin, 33079
Norway3 sites
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Lorenskog, N-1478
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Oslo, 0372
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Trondheim, Trøndelag, 7030
Poland3 sites
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Gdansk, Pomeranian Voivodeship, 80-952
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Poznan, 61-848
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Warsaw, Masovian Voivodeship, 02-097
Belgium2 sites
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Bruges, West-Vlaanderen, 8000
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Genk, 3600
Czechia2 sites
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Prague, 128 08
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Praha, Central Bohemia, 140 00
About this study
Official title: An Open-Label Extension Study to Evaluate the Long-term Safety and Efficacy of ALXN2220 in Adult Participants With Transthyretin Amyloid Cardiomyopathy (ATTR-CM)
The purpose of Study ALXN2220-ATTRCM-302 is to evaluate the long-term safety, tolerability and efficacy of ALXN2220 in adult participants with ATTR-CM treated with ALXN2220 in addition to SoC who have completed Study ALXN2220-ATTRCM-301.
- Being tested
- ALXN2220
- Keywords
- ALXN2220, Cliramitug, NI006, Transthyretin Amyloid Cardiomyopathy, ATTR-CM, Open-Label Extension Study
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ALXN2220Drug
Also called Cliramitug, NI006
To be administered as an IV infusion
| Study group | Role | What they receive |
|---|---|---|
| ALXN2220 | Experimental | Eligible participants will receive ALXN2220 administered IV q4w for a minimum of 12 months and up to 24 months or until participant has access to commercially available ALXN2220 for ATTR-CM, whichever occurs first. Receives: Drug: ALXN2220 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of participants with TEAEs
To evaluate the long-term safety and tolerability of ALXN2220 in participants with ATTR-CM
Measured: Up to 24 months
Secondary outcomes (9)
Total occurrence of ACM and CV clinical events
To evaluate the long-term efficacy of ALXN2220 on ACM and CV clinical events
Measured: Up to 24 months
Total occurrence of CV clinical events
To evaluate the long-term efficacy of ALXN2220 on CV clinical events
Measured: Up to 24 months
Time to ACM
To evaluate the long-term efficacy of ALXN2220 on ACM
Measured: Up to 24 months
Time to first CV clinical event or ACM
To evaluate the long-term efficacy of ALXN2220 on first CV clinical event or ACM
Measured: Up to 24 months
Time to CVM
To evaluate the long-term efficacy of ALXN2220 on CVM
Measured: Up to 24 months
Change from baseline in KCCQ-OS by visit
To assess the long-term efficacy of ALXN2220 on symptoms, functionality, and health-related QoL.
Measured: Up to 24 months
Change from baseline in 6MWT by visit
To assess the long-term efficacy of ALXN2220 on functional capacity
Measured: Up to 24 months
ADA incidence, response categories, and titer
To assess long-term immunogenicity to ALXN2220
Measured: Up to 24 months
NAb incidence and response categories
To assess long-term immunogenicity to ALXN2220
Measured: Up to 24 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Aug 2026
- Study start23 Nov 2027 (estimated)
- Primary completion11 Jul 2030 (estimated)
- Study completion11 Jul 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Transthyretin Amyloid Cardiomyopathy (ATTR-CM)Studies of the same condition, open and under way.
- More trials run by Alexion Pharmaceuticals, Inc.The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 1,180 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Alexion Pharmaceuticals, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07789483
- Sponsor's protocol ID
- D6810C00002
- Other IDs
- ALXN2220-ATTRCM-302, D6810C00002, 166441, 2026-526755-57-00
- Acronym
- LTSAFE-ALXN
- Status last verified
- Aug 2026
- First submitted
- 18 Aug 2026
- Last updated
- 28 Aug 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Alexion has a public commitment to allow requests for access to study data and will be supplying a protocol, CSR, and plain language summaries.
Study at a glance
From the registry record, last updated by the sponsor on 28 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- An Open-Label Extension Study to Evaluate the Long-term Safety and Efficacy of ALXN2220 in Adult Participants With Transthyretin Amyloid Cardiomyopathy (ATTR-CM)
- ClinicalTrials.gov ID
- NCT07789483
- Acronym / sponsor ID
- LTSAFE-ALXN / D6810C00002
- Keywords
- ALXN2220, Cliramitug, NI006, Transthyretin Amyloid Cardiomyopathy, ATTR-CM, Open-Label Extension Study
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 1,180 participants (estimated)
- Lead sponsor
- Alexion Pharmaceuticals, Inc.Industry (pharma, biotech, devices)
- Study start
- 23 Nov 2027 (estimated)
- Primary completion
- 11 Jul 2030 (estimated)
- Study completion
- 11 Jul 2030 (estimated)
- First posted
- 28 Aug 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of Study ALXN2220-ATTRCM-302 is to evaluate the long-term safety, tolerability and efficacy of ALXN2220 in adult participants with ATTR-CM treated with ALXN2220 in addition to SoC who have completed Study ALXN2220-ATTRCM-301.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| ALXN2220 | Experimental | Drug: ALXN2220Eligible participants will receive ALXN2220 administered IV q4w for a minimum of 12 months and up to 24 months or until participant has access to commercially available ALXN2220 for ATTR-CM, whichever occurs first. |
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (3 listed)
- Type of Participant: Participants who have completed the Blinded Treatment Period (including the PC visit) of Study 301.
- Sex and Contraceptive/Barrier Requirements: Male and/or female (according to their reproductive organs and functions assigned by chromosomal complement).
- Informed Consent: Participant, or legally authorized representative where relevant and allowed by law, is willing and able to comply with all study requirements and to provide signed informed consent.
Key exclusion criteria (4 listed)
- Participants who permanently discontinued study intervention in Study 301
- Participants who withdrew full consent during Study 301.
- Medical Conditions: Suspected or known intolerance/allergy to proteins or any components of ALXN2220. Has had a heart transplant or permanent CMAD implantation. Has any new or worsening of existing medical or psychological condition or risk factor that in the opinion of the Investigator or Sponsor might jeopardize participant's safety or compliance with the protocol, or pose any additional risk for the participant, or confound the assessment of the participant or outcome of the study.
- Prior/Concurrent/Future Clinical Study Experience: Current or future participation in another investigational clinical study or intake of investigational drug within 30 calendar days or 5 half-lives of the study intervention, whichever is longer, before signing the ICF, except for study intervention used in Study 301.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ALXN2220Also: Cliramitug, NI006To be administered as an IV infusion | Drug | ALXN2220 |
Primary outcome
Percentage of participants with TEAEs
Time frame: Up to 24 months
To evaluate the long-term safety and tolerability of ALXN2220 in participants with ATTR-CM
9 secondary outcomes
Total occurrence of ACM and CV clinical events
Time frame: Up to 24 months
Total occurrence of CV clinical events
Time frame: Up to 24 months
Time to ACM
Time frame: Up to 24 months
Time to first CV clinical event or ACM
Time frame: Up to 24 months
Time to CVM
Time frame: Up to 24 months
Change from baseline in KCCQ-OS by visit
Time frame: Up to 24 months
Change from baseline in 6MWT by visit
Time frame: Up to 24 months
ADA incidence, response categories, and titer
Time frame: Up to 24 months
NAb incidence and response categories
Time frame: Up to 24 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Aug 2026.
- Individual participant dataSharing planned: Yes. Alexion has a public commitment to allow requests for access to study data and will be supplying a protocol, CSR, and plain language summaries.
Related trials for Transthyretin Amyloid Cardiomyopathy (ATTR-CM)
Not yet recruitingObservational study
Single-arm, Multi-center Study Evaluating the Acceptance and Feasibility of a Digital Remote Monitoring Tool Configured for Patients With ATTR-CM: ACO-Monitor
Transthyretin Amyloid Cardiomyopathy (ATTR-CM)
Not yet recruitingPhase 2
Effect of Trimetazidine on Coronary Flow in Transthyretin Cardiac Amyloidosis
Transthyretin Cardiac Amyloidosis
Active, not recruitingPhase 3
Study of ALXN2220 Versus Placebo in Adults With ATTR-CM
Transthyretin Amyloid Cardiomyopathy
Enrolling by invitationPhase 3
A Study to Evaluate Vutrisiran in Patients With Transthyretin Amyloidosis With Cardiomyopathy
Transthyretin Amyloidosis (ATTR) With Cardiomyopathy
RecruitingPhase 3
CLEOPATTRA: A Research Study to Look at the Effects of Treatment With a Medicine Called Coramitug (NNC6019-0001) in People With Heart Failure Due to Transthyretin Amyloid (ATTR) Amyloidosis
Transthyretin Amyloid Cardiomyopathy (ATTR CM)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
195 sites in 27 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing ALXN2220 in people with Transthyretin Amyloid Cardiomyopathy (ATTR-CM), run by Alexion Pharmaceuticals, Inc. at 195 sites in 27 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 28 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 195 sites in United States, China, Germany, Italy, Spain and 22 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Alexion Pharmaceuticals, Inc., Sponsor (1-855-752-2356, clinicaltrials@alexion.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of participants with TEAEs (time frame: Up to 24 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Aug 2026.