Psoriasis treatment

Psoriasis is incurable, but there are different options to improve the symptoms of the disease, or even to suppress them completely.

There are different therapeutic options, depending on the severity:

  • topical therapy,
  • phototherapy,
  • photochemotherapies using UVA light,
  • conventional systemic treatments and
  • biologics

1. Topical therapy

This treatment covers all measures in which the skin is externally medicated: ointments, creams, solutions or shampoos, for example.

Vitamin-D products

Vitamin-D products specifically act against cornification and interfere with the inflammatory process. They are highly effective and well tolerated at the same time and are currently the standard for the topical treatment of psoriasis.

Tar products

One of the oldest products for the treatment of psoriasis is tar. However, the acceptance is limited in many patients, because the treatment leads to an increased sensitivity of the skin to sunlight; the products have an unpleasant smell and discolouring affect and may not be used during pregnancy and lactation.

Corticosteroids

Corticosteroids (Cortisone-like products) have a predominantly anti-inflammatory effect. Today's corticosteroids have almost no undesirable side effects, provided that they are applied correctly and are very well tolerated.

Dithranol (Cignolin)

Dithranol is a synthetic product, similar to tar.
The treatment is very effective. Dithranol is particularly used for inpatient (day) treatment in hospitals, because the application in outpatient settings is limited due to skin irritations and discolouration of skin and clothing.

Combined vitamin D3 corticosteroid

These preparations contain the two active substances vitamin D3 analogues and corticosteroid, mixed in a single tube. In this combination they lead to faster improvement of the psoriasis than the single substances and are only applied once daily

Tazarotene

Tazarotene, a derivative of vitamin A acid, is no longer commercially available. It has an effect on the formation of scales and inflammation. It may not be used during pregnancy and lactation.

2. Phototherapy

It has been known for a long time that UV irradiation can prevent the proliferation of inflammatory cells on the skin. For example, Leviticus describes even in the Old Testament that lepers experienced healing of their leprosy after sunbathing. Conventional phototherapy of psoriasis fundamentally uses two different principles.

Treatment with UVB light

The experience of many patients shows that sunlight often has a significant positive effect on the psoriasis. The UVB radiation portion of sunlight with a wavelength of 280-320 nm is responsible for this. A wavelength of around 310 nm exhibits the optimum effect; equipment is used for this, which radiates as much UVB light as possible in this wavelength range. The exact dosage is important for preventing an increased risk for developing skin cancer.

Selective UV phototherapy (SUP irradiation)

This uses devices that radiate light of different wavelengths (polychromatic radiation devices), with a maximum emission between 300 nm and 320 nm.

Narrowband UVB therapy (311 nm)

Narrowband UVB therapy uses devices with fluorescent tubes with an emissions peak at 311 nm.

3. Photochemotherapies using UVA light

Psoralen UVA therapy, abbreviated as PUVA therapy, uses a substance before irradiation that makes the skin more sensitive to light (photosensitising substance), applied either in the form of a tablet or externally by a bath or an ointment applied directly onto the skin. 8-methoxypsoralen (8-MOP) is generally used as a photosensitising substance, which makes the skin receptive to UVA light (320-400 nm).

Systemic PUVA therapy

In this treatment form, a photosensitising substance is taken before the irradiation in the form of tablets.

Excimer laser

Targeted UVB therapy of therapy using an excimer laser has been possible for the past 10 years. This made it possible to apply the healing UVB light of wavelength 308 nm in a targeted way directly to the affected skin areas for the first time. Various national and international studies demonstrate that in 85% of cases the skin areas receiving targeted irradiation healed after 10 to 12 treatments.

Cream PUVA therapy

Especially common is this therapy, in which an ointment containing 8-MOP is selectively applied to the psoriasis lesions (typically on hands and feet) is used, where an enhanced UVA photoeffect is desired (psoriasis lesions)

Topical bath-water PUVA

8-MOP may also be dissolved in water and then used as hand or foot-bath as a sensitising agent for the phototherapy. This is then called topical bath-water PUVA.

The psoriasis-free time of the treated areas is comparable to that of conventional phototherapies. For example, there is a relapse-free time after a PUVA/balneo-phototherapy treatment of approx. nine to 12 months.

The most important benefits are:

  • Individual dosage (adjusted to the thickness of the psoriatic plaque)
  • Leaving out the healthy skin by targeted light irradiation (therefore "targeted UVB therapy" in English language literature)

In 2006 the targeted UVB therapy using excimer laser was included in the S3 guideline for psoriasis and it is specifically recommended for small area psoriasis affecting a body surface area of below 10%. Therefore, it is particularly suitable for:

  • Clearly delineated small-scale plaques, for example elbows, knees, calves
  • Problem areas, such as navels, intertriginous areas (flank, abdominal folds, arm pits, anal region)
  • Plaques on the scalp

4. Conventional systemic treatments

In patients with moderate or severe psoriasis a topical or phototherapy alone can often not bring about satisfactory improvement. In these cases, systemic treatments will be necessary: Additional treatments with medications in the form of tablets, injections or infusions.

A distinction is made between:

  • conventional medications, not produced by genetic modification
  • biologics, substances produced by genetic modification

Many criteria must be considered, since the decision in favour of any potential medication is strongly dependent on the individual's state of health, for example:

  • type and location of the psoriatic lesions
  • pre-existing conditions and co-morbidities
  • existing contraindications
  • interactions with concomitant medication
  • the presence of a psoriatic arthritis
  • personal circumstances (e.g. desire to have children).

These drugs should be used only after a detailed consultation and examination by physicians, who have experience with these treatments.

The following conventional systemic treatments have been included in the S3 guideline Psoriasis therapy and are mostly used in Switzerland:

Apremilast

Apremilast, approved since July 2015 for the treatment of moderate to severe common psoriasis, works by reducing the activity of the so-called phosphodiesterase 4, a natural substance in the body's cells. This helps to reduce the inflammation factors in the inflammatory cells, which play an important role in psoriasis.

The substance is taken in the form of tablets and leads to a significant improvement of the psoriasis on the skin, scalp and nails and also leads to a rapid reduction of the itching. Due to its efficacy in psoriatic arthritis, apremilast also helps when joints are involved.

Fumaric acid ester

Fumaric acid esters have been approved in Germany since 1995 for the treatment of common psoriasis. They are dispensed in the form of tablets with gradually increasing doses to adapt the body to the medication. The S3 guideline confirms good efficacy of the fumaric acid esters in induction therapy and also in long-term therapy because of their favourable benefit-risk profile.

Methotrexate

Methotrexate is approved in Switzerland for the treatment of common psoriasis and is used either in the form of tablets, or, more commonly, as an injection once per week (better bioavailability). Since methotrexate also works well in many cases of psoriatic arthritis, it is also the preferred treatment in cases involving joints.

Ciclosporin

Ciclosporin, a ring-shaped peptide with immunosuppressant effect, has been approved in Germany as a medication for the treatment of the psoriasis since 1993. The S3 guideline for psoriasis treatment recommends ciclosporin for induction therapy in moderate to severe common psoriasis in adults who do not show the desired response to a treatment with topical therapy and/or phototherapy.

Treatment options include:

  • Short-term therapy with capsules (generally) for some months, which are repeated in intervals
  • Continuous long-term therapy (less common) for a period of one to two years

Retinoids

Since the 70s retinoids, vitamin A derivatives, are used in the treatment of common psoriasis and today they are used mostly in the treatment of hands and feet of the following types:

Pustular psoriasis (forming pustules)
Hyperkeratotic psoriasis (with severe cornification)
Within the EU there are additional medications in use, which are not approved in Switzerland for the treatment of psoriasis. Thanks to their good efficacy, they are used in individual cases for psoriasis treatment, following individual cost approval by the respective health insurance provider.

5. Biologics

This new class of medications is produced by biotechnology, in order to enable intervention in the immunological processes in the body. They mainly block the inflammatory processes, by acting as antagonists of the so-called cytokines. Cytokines are neurotransmitters that trigger or control inflammation, and which are transmitted by the immune system's scavenger cells, the macrophages. These neurotransmitters include, among others, the tumour necrosis factor alpha (TNF-α) and the interleukin 12/23 and/or interleukin 17.

Thanks to the discovery that the cytokine TNF-α plays a key role in the development and maintenance of inflammatory processes in moderate to severe plaque psoriasis, innovative and effective medications have been developed over the past few years. TNF-α blockers facilitate targeted intervention in the inflammatory response and may suppress it. The skin symptoms often subside within a few weeks, and in some cases even completely. Newer biologics target IL-12/23 and, even more effectively, IL-17.

Biologics may be used in patients from the age of eight with moderate and severe plaque psoriasis, if conventional treatments have shown insufficient success, may not be used for various medical reasons, or were not tolerated.

In contrast to the classical systemic therapies, the biologics work very quickly, and therefore many patients report an improvement of symptoms within only a few weeks from the start of treatment.

Biologics are proteins, which cannot be taken as tablets because they would be destroyed by the gastric acid. Therefore, they are administered as an injection, either below the skin (subcutaneous) or by the doctor as an infusion into the vein (intravenously).

Treat to Target

According to larger studies a psoriasis treatment is particularly successful if the patient and the treating physician have on one hand, clearly defined the patient's expectations, and the realistic aims of the therapy on the other hand. Dermatologists, who are PsoriNet members, define these aims jointly with the patient. The improvement of the patient's quality of life is the main focus and not just the skin specific treatment aims. Co-morbidities, such as high blood pressure, excess weight, depression, etc. are also carefully monitored.