Biosimilars vs. Biologics for Treating Psoriatic Disease

Biosimilar drugs are manufactured similarly to biologic drugs. Like biologics, they are derived from living cells (human, animal, or bacterial) in a lab setting. Many people think biosimilars are generic versions of biologics. However, this is not the case, as it is impossible to accurately copy a drug made from living cells.

For consumers, the most important difference between biologics and biosimilars is price. One of the main arguments for using biosimilars is the cost savings for both patients and insurance companies. For example, a 2017 report from the RAND corporation predicted that by 2026, biosimilars could reduce biologic spending in the U.S. by $54 million.

While biologic drugs are still being developed and going through the FDA approval process, several biosimilars have been created to treat autoimmune diseases, including psoriatic disease. In 2016, the FDA approved three biosimilars to treat plaque psoriasis and psoriatic arthritis.

This article discusses the relationship between biologics and biosimilars along with how they compare in cost. It also covers the side effects associated with biosimilars and why your doctor may or may not prescribe them for your psoriatic disease.

Relationship Between Biosimilars and Biologics

Before the FDA approves a biologic, the product is rigorously tested and evaluated with large randomized controlled trials, in which participants are randomly assigned to take either the biologic or a placebo.

These trials take place at medical research centers located in multiple locations with diverse population groups. This allows researchers to ensure the biologic is safe and effective for people from diverse genetic, ethnic, environmental, and cultural backgrounds.

The biologic is only approved once it has met the FDA's high standards for safety and effectiveness.

Biosimilars undergo rigorous testing and evaluation to ensure their safety as well. But because they are created to replicate biologics, they don't have to prove their effectiveness with the same sorts of randomized controlled trials.

Instead, the FDA approves a biosimilar when the drug is established as "highly similar" with "no clinically meaningful differences" compared to an existing FDA-approved biologic product.

Highly similar means the structure and function of the biosimilar product are the same as the original biologic product. No meaningful clinical differences means the biosimilar has no differences in safety and effectiveness, as noted in clinical studies of the similar biologic.

FDA-Approved Biosimilars

As of 2022, the FDA has approved the following biosimilars that correspond to biologic drugs used to treat psoriasis and psoriatic arthritis:

• Biosimilars to the drug Humira (adalimumab): Amjevita (adalimumab-atto), Abrilada (adalimumab-afzb), Cyltezo (adalimumab-adbm), Hadlima (adalimumab-bwwd), Hulio (adalimumab-fkjp) and Hyrimoz (adalimumab-adaz)
• Biosimilar medicine to Enbrel (etanercept): Erelzi (etanercept-szzs) and Eticovo (etanercept-ykro)
• Biosimilars to Remicade (infliximab): Avsola (infliximab-axxq), Inflectra (infliximab-dyyb), Ixifi (infliximab-qbtx) and Renflexis (infliximab-abda)

Costs and Access

The price of each biosimilar drug will vary but patients can typically expect them to cost less than the biologic version. One reason for the cost difference is that biosimilar drugs are created by “reverse engineering” a biologic product.

While they still undergo a rigorous research, development, and testing process, it’s less than what was required to make the original biologic drug. That’s why it generally costs less to produce a biosimilar than it did to create the biologic it was based on.

When medications are cheaper, they are more accessible to patients and reduce the overall economic toll. However, that's assuming that the biosimilar drugs exist, have been approved, and are available to consumers.

For example, people with psoriatic disease in the U.S. don't have access to some biosimilars available in Canada, Australia, and many European countries due to patent disputes that have held up the approval process.

Who Should Not Take Biosimilars?

Biosimilars are prescribed to treat advanced cases of a disease, including psoriatic conditions. You may need to take special steps to prevent infection when you are taking biosimilars, as your immune system won’t be as strong. For example, your healthcare provider might instruct you not to get a “live” flu vaccine or avoid friends and family members who are sick.

If your healthcare provider wants to prescribe a biosimilar to treat your moderate-to-severe psoriatic disease, you will need to be screened for tuberculosis (TB) and other infectious diseases before you can start the medication.

Specific biologics and biosimilars used to treat psoriatic conditions provide a list of infections or conditions, such as fungal infections and tuberculosis, that patients taking the drug should watch for. If you develop these infections, you should not take biosimilar drugs.

If you are pregnant or nursing, you may need to stop taking a biosimilar drug. While some biosimilars might be safe if you are pregnant or breastfeeding, the research is limited. It's not yet clear how different biosimilars could affect fetal development, influence the course of pregnancy and delivery, or pass into breastmilk.

If you have psoriatic disease and take biosimilars, talk to your healthcare provider if you plan to become pregnant.

Risks and Side Effects

The risks and side effects of biosimilars are the same as those associated with their biologic counterparts. If you are thinking about a biosimilar, you should talk to your healthcare provider and weigh the risks and benefits of taking these medications.

Each biosimilar will have its own list of side effects, but some of the more commonly experienced include:

• Headaches
• Abdominal pain
• Flu-like symptoms
• Upper respiratory infections
• Skin reaction where the injection or IV was given

Let your healthcare provider know if you experience side effects from biosimilars, especially if they persist after a few weeks of treatment.

One of the most significant risks of biosimilars and biologics is that they suppress your immune system, which means you'll be at an increased risk for infections (some of which can be serious).

If you develop signs of infection when taking biosimilars or biologics, call your healthcare provider right away.

Using Biosimilars With Other Treatments

Before starting a biosimilar or biologic, tell your healthcare provider about all the medications, vitamins, and supplements you are currently taking.

Much like biologics, biosimilars are usually safe to use with topical treatments and phototherapy for psoriasis. However, research has suggested there are some cases when mixing treatments is not advised.

For example, a 2013 study found that using Inflectra (a biosimilar of Remicade) with phototherapy may increase skin cancer risk. 

Other drugs commonly used to treat psoriatic disease, such as methotrexate, have been found to be safe to take with biologics and biosimilars.

Summary

Biosimilars are often less expensive than biologics in part because they don't have to undergo the same large randomized trials that biologics do.

Biosimilars gain FDA approval when they demonstrate that they are highly similar in structure, function, safety, and effectiveness to their biologic counterparts.

Like biologics, biosimilars work by suppressing immune system function. For this reason, biosimilars may not be right for people who have an increased risk of infection.

A Word From Verywell

If you are currently using a biologic, ask your healthcare provider if there is a biosimilar to your current biologic available and if it could be a safe and effective option for you.

You should ask your healthcare provider about how the biosimilar will be included as part of your treatment plan, and about safety, effectiveness, and cost. You will also want to find out if your insurance will cover the cost of a biosimilar. If it currently does not, ask when coverage will be available. 

As research continues and patent litigations are resolved, new biosimilars are expected to become available in the years to come. Once these drugs are approved and hit the market, you'll have more options for treating psoriatic disease.