Compassionate Use Protocol for the Treatment of Autoinflammatory Syndromes

Inclusion Criteria:

- Are ≥17.5 months of age (or are ≥6 months of age with Aicardi-Goutières Syndrome
[AGS]). Participants younger than 17.5 months of age can be considered for
enrollment after discussion with the sponsor.

- Have systemic signs and symptoms of inflammation as manifested by the presence of
two or more of the following symptoms: rash, fever, musculoskeletal pain, headache,
fatigue, weakness, respiratory/breathing symptoms, or ulcers/ischemic lesions.

- Have an average daily Diary Score of ≥0.5 (CANDLE Diary; used also for
CANDLE-related conditions, AGS Diary) or ≥1.0 (SAVI) or ≥1.0 exclusive of headache
and fever symptoms (JDM Diary) assessed over at least 2 weeks prior to entry, if
available. Otherwise, participants can complete the diary after study consent is
signed during the screening period and meet the inclusion criteria for enrollment
into the study.

- Are ≥8.5 kilogram (kg) in body weight. Participants weighing less than 8.5 kg can be
considered for enrollment after discussion with the sponsor.

- Have been previously treated with at least 1 biologic therapy and, in the opinion of
the investigator, did not respond or are no longer responding to therapy. If the
participant has been diagnosed with CANDLE, Nakajo-Nishimura Syndrome (NNS), SAVI,
AGS, or an equivalent syndrome, the need for previous biologic therapy is not
required.

- Require treatment with oral corticosteroids (≥0.15 milligrams per kilogram per day
[mg/kg/d] of prednisone or its equivalent) for control of systemic signs and
symptoms of their chronic inflammatory disease for at least 2 weeks prior to study
entry, or in the opinion of the investigator, have failed an adequate course of
steroids. Treatment with or failure of treatment with steroids is not required for
participants with AGS or a confirmed genetic diagnosis of CANDLE or SAVI.

- Have had previous documented elevations in acute-phase reactants (for example, high
sensitivity C-reactive protein) considered to be the result of the inflammatory
disease (participants with CANDLE or CANDLE-related conditions only).

- Have the ability to provide informed consent or have legal representative who is
willing and able to provide written informed consent, provided that assent is
obtained from participants at an age-appropriate level.

Exclusion Criteria:

- Have received an immunosuppressive biologic agent/monoclonal antibody within 4
half-lives prior to entry, for example, anakinra (4 half-lives=18 hours); etanercept
(4 half-lives=18 days); infliximab; adalimumab (4 half-lives=36 days); use of
intravenous immune globulin (IVIg) is permitted.

- Are pregnant or nursing at the time of entry.

- Are females of childbearing potential (women >12 or who have had at least 1
menstrual period regardless of age) who are sexually active and who do not agree to
use 2 forms of highly effective methods of birth control or remain abstinent during
the study and for at least 28 days following the last dose of investigational
product.

- Are sexually active males who do not agree to use 2 forms of highly effective birth
control with female partners of childbearing potential or remain abstinent during
the study and for at least 28 days following the last dose of investigational
product.

- Have had symptomatic herpes zoster infection within 12 weeks prior to entry or
during the screening period.

- Have a history of disseminated/complicated herpes zoster (for example,
multidermatomal involvement, ophthalmic zoster, central nervous system [CNS]
involvement, postherpetic neuralgia).

- Have evidence of active infection, at the time of entry or during the screening
period, that in the opinion of the investigator, would pose an unacceptable risk for
participating in the study.

- Have a history of active hepatitis B (HBV), hepatitis C (HCV), or human
immunodeficiency virus (HIV).

- Have documented high titer autoantibodies suggestive clinically of autoimmune
diseases other than severe JDM.

- Are immunocompromised and, in the opinion of the investigator, are at an
unacceptable risk for participating in the study.

- Have had a serious systemic or local infection (including an infectious
mononucleosis-like illness or herpes zoster) within 12 weeks prior to entry or
during the screening period.

- Have been exposed to a live vaccine within 12 weeks prior to entry or are expected
to need/receive a live vaccine (including herpes zoster vaccination) during the
course of the study.

Note: Investigators should review the vaccination status of the participants and follow
the local guidelines for vaccination with nonlive vaccines intended to prevent infectious
disease prior to entering participants into the study.

- Have had household contact with a person with active tuberculosis (TB) and did not
receive appropriate and documented prophylaxis for TB.

- Have a serious and/or unstable illness that, in the opinion of the investigator,
poses an unacceptable risk for the participant's participation in the study.

- Have an estimated glomerular filtration rate (eGFR) based on the most recent
available serum creatinine of <40 milliliters/minute/1.73 per square meter.

- Have or have had a history of lymphoproliferative disease; or signs or symptoms
suggestive of possible lymphoproliferative disease, or active primary or recurrent
malignant disease; or been in remission from clinically significant malignancy for
<5 years.

Note: Participants with resolved cervical dysplasia, or no more than 3 successfully
treated basal-cell carcinoma of the skin, may participate in this study.

- Have a history of chronic alcohol abuse or intravenous (IV) drug abuse within the 2
years prior to entry.

- Are unable or unwilling to make themselves available for the duration of the study
and/or are unwilling to follow study restrictions/procedures.

- Are currently enrolled in, or discontinued within the last 30 days from a clinical
trial involving an investigational product or non-approved use of a drug or device
(other than the investigational product used in this study), or concurrently
enrolled in any other type of medical research judged not to be scientifically or
medically compatible with this study.