How Long Does It Take Avsola to Work? Understanding the Timeline for Relief

October 8, 2025 •

4 min read

While some patients may notice an initial improvement within weeks of starting Avsola, full therapeutic response often requires the completion of the initial induction phase, which spans several weeks. The time it takes to experience the full benefits of Avsola can vary significantly depending on the treated condition and individual patient factors.

Quick Summary

The onset of action for Avsola varies by individual and condition, with initial improvements sometimes appearing within weeks. A full response is typically assessed after the initial 14-week induction phase.

Key Points

Induction Phase is Key: Avsola requires a series of initial infusions to establish therapeutic levels before long-term effectiveness can be assessed.
Assessment Point is Week 14: For many conditions like Crohn's, clinicians typically evaluate the patient's response around Week 14, and may discontinue treatment if no significant improvement is observed.
Initial vs. Full Response: Some patients may experience initial symptom relief within weeks of the first infusion, while others may need several months to reach full remission or maximum benefit.
Condition-Dependent Timeline: The onset of action and time to full effect varies by indication; for example, RA often has a longer timeline for full effect compared to conditions like Crohn's.
Factors Affecting Response: Individual patient factors such as disease severity, metabolism, concurrent medications, and adherence to the infusion schedule can all influence the treatment timeline and outcome.
Biosimilarity to Remicade: As a biosimilar to Remicade (infliximab), Avsola is expected to have a comparable onset of action and clinical effectiveness.

What is Avsola and how does it work?

Avsola (infliximab-axxq) is a biosimilar medication, meaning it is highly similar to an existing FDA-approved biologic drug, Remicade (infliximab). It is a monoclonal antibody that targets and neutralizes tumor necrosis factor-alpha (TNF-α), a protein that plays a key role in the body's inflammatory responses. By blocking excess TNF-α, Avsola helps reduce inflammation and its associated symptoms in various autoimmune diseases.

Because of its biological mechanism, Avsola's effects are not instantaneous. The medication needs time to build up in the body and interrupt the underlying inflammatory cascade, which is why an initial 'induction' phase is necessary. During this phase, patients receive a series of infusions spaced over several weeks to achieve a steady therapeutic level of the drug.

The induction phase: The first 14 weeks

For most conditions, the induction phase is a critical period that establishes the drug's effectiveness. The standard schedule for most conditions includes infusions at specific intervals. This concentrated initial period is designed to get the patient's condition under control. The FDA label for Avsola notes that for Crohn's disease, patients who do not respond by Week 14 are unlikely to respond with continued dosing. This 14-week mark serves as a key checkpoint for assessing the treatment's success.

Timeline for specific conditions

The onset of action and time to clinical improvement with Avsola can differ based on the specific autoimmune disease being treated. Here are general timelines based on clinical experience with infliximab products:

Crohn's Disease (CD): For patients with moderately to severely active CD, clinical trials indicate that response rates are assessed by week 14, though some patients may experience improvement much sooner. Some patients have reported feeling better within days of their first infusion.
Rheumatoid Arthritis (RA): In RA, Avsola is typically used in combination with methotrexate. Patients might start to feel better within 4 to 6 weeks, but it can take 3 to 6 months to see the full effect. If the initial treatment plan is not effective, the doctor may make adjustments.
Ankylosing Spondylitis (AS): Clinical evidence with infliximab shows that a significant number of patients experience at least a 50% improvement in disease activity, with a maintenance regimen starting after the induction phase. Long-term efficacy is maintained with regular infusions.
Ulcerative Colitis (UC): Similar to Crohn's disease, the induction phase precedes a maintenance phase at regular intervals. A full clinical assessment would be conducted at or after the 14-week mark.
Plaque Psoriasis and Psoriatic Arthritis (PsA): For both conditions, Avsola is administered using the same induction schedule as many other indications, with a maintenance infusion after the initial phase. The clinical response is evaluated based on symptom improvement over time, and some patients may take several months to achieve a complete response.

Factors that influence the timeline

Several factors can affect how quickly and effectively Avsola works for an individual:

Disease severity: Patients with more severe or active disease may take longer to respond to therapy compared to those with less severe symptoms.
Combination therapy: For conditions like rheumatoid arthritis, Avsola is used with methotrexate. This combination can enhance the effectiveness and potentially influence the time to response.
Individual metabolism: Every person's body processes medication differently. Factors such as weight and metabolic rate can influence how quickly the drug reaches and maintains therapeutic levels.
Antibody formation: Some patients may develop antibodies against the infliximab-axxq protein, which can reduce its effectiveness over time. This is one reason why combination therapy with methotrexate is often used for RA, as it can help prevent antibody formation.
Missed infusions: Adhering to the prescribed infusion schedule is crucial for maintaining the drug's effectiveness. Missing doses can disrupt the therapeutic levels and delay or diminish the response.

Avsola Onset of Action by Condition


Condition	Typical Time to Initial Improvement	Time to Evaluate Full Response	Notes
Crohn's Disease	Within a few weeks; some report relief after 1st dose	As early as Week 14; discontinuation considered if no response	Response can vary; assessment at Week 14 is a clinical guideline.
Rheumatoid Arthritis	4-6 weeks; full effect may take 3-6 months	Up to 6 months	Used with methotrexate; dosage adjustment possible if response is incomplete.
Ankylosing Spondylitis	Within weeks, noticeable improvement often by Week 6	After the induction phase; maintained with regular infusions	Significant improvement noted in clinical trials.
Ulcerative Colitis	Assessment at Week 14	After the induction phase; maintained with regular infusions	Similar induction timeline to Crohn's.
Psoriatic Arthritis	Varies; follow-up starts after Week 6	Maintained with regular infusions	Can be used with or without methotrexate.

Conclusion

While some patients may feel the effects of Avsola relatively quickly after the first infusion, the full therapeutic benefit is generally not realized until after the initial induction phase, around 14 weeks. The specific timeline can be influenced by the condition being treated, disease severity, and individual patient characteristics. It is important to work closely with a healthcare provider to manage expectations, track progress, and determine the long-term effectiveness of the treatment. Failure to respond by the 14-week mark may lead to a change in therapy, as per prescribing information.

For more detailed information, consult the Official Avsola Prescribing Information provided by Amgen.

Frequently Asked Questions

Some patients may start to feel a difference as early as a few weeks after their first Avsola infusion. For some individuals with conditions like Crohn's, improvements have been reported even a few days after the initial dose.

The 14-week mark is often a key checkpoint for assessing Avsola's effectiveness, especially for Crohn's disease. If a patient does not show a response by this time, their doctor may consider discontinuing the medication and exploring other options.

For rheumatoid arthritis, Avsola is used in combination with methotrexate, and the full effect can take longer to develop. While initial relief may occur in 4-6 weeks, a complete and sustained response may require up to 3 to 6 months of treatment.

You should not attempt to alter your infusion schedule or other aspects of your treatment plan without consulting your healthcare provider. Adhering strictly to your prescribed schedule and following all your doctor's instructions is the best way to ensure the medication works as intended.

Yes, as a biosimilar, Avsola is designed to have no clinically meaningful differences from Remicade (infliximab). This means its expected onset of action and efficacy timeline should be comparable to the reference product.

If you experience a loss of response after an initial improvement, it is important to discuss this with your doctor. They may consider making adjustments to your treatment plan.

If there is no significant response by Week 14, it is important to communicate this with your doctor. According to prescribing information, patients in this situation are unlikely to respond to continued Avsola, and alternative therapies should be discussed.