Clinical Drug Experience Knowledgebase

Rheumatoid arthritis (RA) is a systemic, chronic, inflammatory disorder leading to accelerated joint inflammation causing pain, swelling and limited motion of joints, ultimately leading to the development of joint destruction and deformity in the majority of patients. Virtually all peripheral joints can be affected by RA, although the most commonly affected joints are those of wrists, hands, knees, and feet.

During the last decade, treatment with biologicals (e.g. TNF-inhibitors), together with improved timing and dosing of conventional therapy, has significantly improved the outcome in a significant proportion of RA patients. The advent of biologicals and implementation of more intensive treatment protocols has significantly improved the outcome in a significant proportion of RA patients and prevented disabilities. However, drug-free remissions are still rare and hence most RA patients require continued immunosuppressive treatment which predisposes them to potentially serious infections.

Also up to 50% of RA patients continue to suffer from symptomatic disease. Intra-articular glucocorticoids are often used in these patients, e.g. when single joints are inflamed. The duration of their effect is however variable. It regularly occurs in clinical practice that reasonable clinical remission in rheumatoid arthritis patients is achieved with current treatment options, but that one or more joints still display persistent signs of inflammation while the inflammation of other joints has been greatly reduced. This means that for the joint(s) still affected by active inflammation other therapies are required.

There is thus a large unmet need for additional RA therapies with good tolerability and efficacy profiles that can be used in patients who are not eligible for standard treatment, and in those who despite standard treatment suffer from inflamed joints. Local gene therapy with IFN-β could be a potential treatment to fulfil this unmet need; the selection of IFN-β as the therapeutic protein is based on the notion that IFN-β has anti-inflammatory, bone and cartilage protective effects, which have been extensively demonstrated in non-clinical studies.

Osteoarthritis (OA) is a multifactorial joint disease that involves degeneration of articular cartilage, causing pain, limited range of motion of joints and thereby disability. Although aetiology is largely unknown, important factors such as genetic pre-disposition, mechanical and biochemical stress are known to play a role in this multi factorial disease. Ligaments, menisci, and muscles can also be affected, and osteophytes may develop, causing additional pain.

Current treatment options of OA are restricted to symptomatic treatment to mitigate pain, rather than proactively preventing progression of disease. These treatment options in early stage OA consist of non-pharmacological therapies, such as advice in joint strain in periods of complaints, which can potentially be aided by splint therapy and targeted exercises. In a later stage of OA, systemic or local topically applied analgesics are commonly utilized. Another option is the injection of compounds in the joints, but neither corticosteroids nor hyaluronic acid injections have proven to significantly improve pain compared to placebo. Surgical options in hand OA exist, but are only recommended in patients with severe motion restriction and these surgeries may not be beneficial to all patients Although there are a number of options aiding patients with OA, currently there are less treatment options for osteoarthritis (OA) than for RA and most focus on mitigation of pain. In both RA and OA, this means that for the joint(s) still affected by active inflammation other therapies are required.

ART-I02 is an investigational new drug, expressing human IFN-β from a recombinant (r) adeno-associated virus type 5 (rAAV5) β under the influence of a promoter, which is induced by an inflammatory stimulus. Due to the relapsing nature of RA, therapeutic expression should be maximal during flare-ups of the disease. This is achieved by employing the NF-kB responsive promotor to regulate expression of IFN-β. Under inflammatory conditions, the NF-kB responsive promoter will be activated in the synovium and will upregulate the expression of hIFN-β and turned down during remission. In this way, transgene expression can be controlled, following the intermittent course of disease.

In this phase I open label, dose escalating study the safety of a single intra-articular ART-I02 injection in patients with RA or OA and active arthritis of the metacarpophalangeal (MCP), proximal interphalangeal (PIP), or distal interphalangeal (DIP) joint with an indication for surgical intervention which includes removal of the synovium. In a two-phase staggered dose escalation design, dosing will start with a low dose (1.2x1012 vg/ MCP joint, 0.6x1012 vg/ PIP joint or 0.3x1012 vg/ DIP joint) and progress to the highest dose of 1.2x1013 vg/ MCP joint, 0.6x1013 vg/ PIP joint or 0.3x1013 vg/ DIP joint. Three patients will be enrolled at each of the two dose levels. Enrolment of a subject within each of the two cohorts will not proceed until the safety data through day 7 from the previous subject have been reviewed/evaluated by the investigator. After dosing of the last subject in cohort I and II, a dosing pause of two weeks is included to allow an assessment of the safety data by the Data Review Committee. All available safety data including a minimum of 2 weeks of data (safety and tolerability data through day 14 post ART-I02 administration) from the 3rd patient of cohort I and II (medical history, vital signs, physical examination, laboratory parameters, ECG and adverse events) will be reviewed. Only after a thorough assessment of these safety data enrolment in the next cohort will continue.

In cohort III six patients will be administered the highest safety dose of ART-I02 as determined in the previous dose escalating cohorts (cohorts I and II). Cohort III is added to the study to substantiate the safety profile of the highest tolerated dose of ART-I02.

Subjects will be followed for 24 weeks after the single intra-articular injection of ART-I02 for safety. Although the study is not designed to demonstrate a clinical effect, (clinical) efficacy parameters will be evaluated. After this period subjects will be included in a long term follow-up study for another 4.5 years to assess long term safety.

The consideration to treat one joint in this clinical study is that it provides the opportunity to examine the administration of a single dose at the site where the promoter is activated and where the therapeutic protein IFN-β is required. Patients who have an indication for a surgical intervention for the affected target joint will be recruited for this study. With this approach a possible benefit for the patients can be obtained (postponing the surgical intervention), while at the same time it provides the opportunity to mitigate risk caused by untoward effects due to persistence of the vector (planned surgical intervention will be carried out earlier).