Brand Name: Siliq
Generic Name: brodalumab
Medication class: Human interleukin receptor antagonist
Similar drugs: Stelara (ustekinumab), Cosentyx (secukinumab), Taltz (ixekizumab)
Manufacturer: Valeant Pharmaceuticals International, Inc.
FDA approval date: February 16, 2017
What is Siliq and how does it work?
Siliq is a human monoclonal antibody that is used to treat plaque psoriasis, which is an autoimmune disease. Patients with this condition usually develop abnormal patches of skin that are thick, red, and scaly. One of the causes of plaque psoriasis is an immune response that triggers the release of compounds(cytokines) that cause inflammation. This immune response involves an interaction between cytokines that are called interleukins, and their receptor, interleukin-17 receptor A (IL-17RA). Siliq works by selectively binding to and inhibiting this receptor, preventing its interaction with interleukins (IL-17A, IL-17F, IL-17C, IL-17A/F and IL-25). By preventing these interactions, it puts a halt to the release and recruitment of the inflammatory compounds responsible for causing plaque psoriasis.
What is Siliq used for treating?
Siliq is used to treat moderate to severe plaque psoriasis in adults have either failed to respond or have lost response to other medications.
How effective is Siliq?
Siliq was studied in three studies that included 4,373 adult subjects with moderate to severe plaque psoriasis for at least 6 months. Two of the studies compared Siliq’s efficacy against Stelara (ustekinumab) or placebo. The third study compared Siliq versus placebo. The following co-primary endpoints were used:
1) PASI 75 (Psoriasis Area and Severity Index): the proportion of subjects who achieved at least a 75% reduction in PASI score
2) sPGA (Static Physician’s Global Assessment) score of 0 (clear) or 1 (almost clear), and at least a 2-point improvement from baseline.
3) PASI 100: (Psoriasis Area and Severity Index): the proportion of subjects who achieved at least a 100% reduction in PASI score
All three studies evaluated PASI scores from baseline to the end of a 12-week trial. The results are as follows:
Amongst the patients who received Siliq, 84.7% achieved PASI 75, and 78.3% achieved an sPGA score of 1 or 0. For patients who received Stelara, 69.5% achieved PASI 75 and 59% scored 1 or 0 on sPGA. Siliq showed significant efficacy in comparison to the placebo treatment group in which only 5.7% of patients achieved PASI 75 and 3% achieved an sPGA score of 1 or 0. PASI 100 was achieved by 41% of patients treated with Siliq versus 20.5% of patients who received Stelara.
Interesting facts about Siliq
What are the side effects of Siliq?
The most commonly reported side effects of Siliq were:
Serious but rare side effects include:
What is the dosage of Siliq?
The recommended dose is 210 mg injected subcutaneously at weeks 0, 1, and 2, followed by 210 mg every two weeks thereafter. Doctors should consider stopping Siliq if the response is not enough after 12 to 16 weeks of treatment. Treatment beyond 16 weeks in patients who have not responded enough may not provide additional benefit.
Preparations For Use: Siliq is available as single-dose prefilled syringes containing 210 mg/1.5 mL solution. The first dose should be given by a healthcare provider, allowing for the patient to be trained on how to self-administer the subsequent doses. Prior to use, it is important to make sure that the solution is clear, colorless to slightly yellow, and at room temperature. Siliq should be injected at a 45° angle into the clean undamaged skin of the abdomen, thighs, or upper arms.
What are the warnings and precautions for Siliq?
Black Box Warning: Siliq is associated with suicidal ideation and behavior. Patients should stop using Siliq immediately if they experience these symptoms.
Infections: Since Siliq is a human monoclonal antibody, it may lessen the immune system’s ability to fight infections. Patients should be warned of an increased risk of infection, and to report any signs or symptoms of infection to their healthcare provider.
Crohn’s Disease: Siliq is contraindicated in patients with Crohn’s disease, as it may worsen the condition. Siliq may also increase a person’s risk of getting Crohn’s Disease.
Tuberculosis (TB): Siliq is also contraindicated in patients with an active TB infection. For patients with latent tuberculosis, the infection should be treated prior to initiating Siliq. It is advised that all patients be screened for TB prior to receiving this drug.
Pregnancy and Lactation: There are no human data available on the safety of Siliq in pregnant women. Since human antibodies are known to cross the placenta, it is recommended that patients tell their prescriber if they are pregnant or planning on becoming pregnant. It is also unknown if Siliq is excreted through breast milk.
What are the drug interactions for Siliq?
Drug interactions listed for Siliq include live vaccines and CYP450 substrates. During chronic inflammation, there is an increase in cytokines (IL-1, IL-6, IL-10, IFN, TNF), which can alter the formation of CYP450 enzymes. CYP450 enzymes are essential for breakdown and elimination of many drugs. Since Siliq blocks the action of cytokines, this may normalize formation of CYP450 enzymes. Blood levels of drugs that are broken down by CYP450 enzymes should be monitored, especially those that have a narrow therapeutic index (e.g., warfarin, phenytoin).
Storage: Siliq prefilled syringes should be kept in its original packaging and refrigerated between 36°F to 46°F (2°C to 8°C). At room temperature up to a maximum of 77°F/25°C, Siliq is only stable for 14 days and must be used within that time frame. Once Siliq has been allowed to come to room temperature, it cannot be re-refrigerated. Do not freeze or shake, and keep away from sunlight and children.
What is the cost of Siliq?
Pricing for Siliq has not been announced.
Siliq Prescribing Information. 2017. Valeant Pharmaceuticals North America LLC.Accessed 2/16/17.
Brodalumab Injection. FDA DODAC Meeting documents, 2016. Valeant Pharmaceuticals North America LLC. Accessed 2/16/17.
FDA News Release: FDA Approves new psoriasis drug. 2017. U.S. Dept. of Health and Human Services. Accessed 2/16/17