Prospektive Versorgungsforschungsstudie zur Therapie mit Immunglobulinen (SIGNS)

Management of patients with malignancies and secondary immunodeficiencies treated with immunoglobulins in clinical practice: Long-term data of the SIGNS study

OBJECTIVE

We aimed to describe the current management and outcomes of patients with secondary immunodeficiencies (SID) on intravenous (IV) or subcutaneous (SC) immunoglobulins (IG) as maintenance therapy to prevent infections.

METHODS

Non-interventional, prospective study (average follow-up 20.5 months).

RESULTS

Of the 307 SID patients (mean age 63.7±14.4 years, 52% males, in 31% IG newly initiated), 95.4% received IV IG (mean dosing interval 4.6 weeks, average dose 199 mg/kg per 4 weeks) and 4.6% were treated with SC IG (2.6 weeks, 343 mg/kg per 4 weeks). Median IG through level at first documentation was 5.8 g/L and did not differ between IV and SC treatment or between underlying malignancies. In 24.1% of patients, treatment was interrupted temporarily, over a mean of 11.6±6.3 months. In patients with newly initiated IG treatment the 82% overall infection rate prior to treatment dropped to 21% at 1 year.

CONCLUSIONS

Under clinical practice conditions, IG replacement therapy in SID patients was feasible, diminished infection rates and improved quality of life. Average IG doses were relatively low. Tolerability of IV IG treatment was excellent.

Treatment of patients with multifocal motor neuropathy with immunoglobulins in clinical practice: the SIGNS registry

OBJECTIVES

The management of patients with multifocal motor neuropathy (MMN) under everyday clinical conditions has been insufficiently studied. We therefore collected comprehensive observational data on patients with MMN who received intravenous (IV) or subcutaneous (SC) immunoglobulins (IGs) as maintenance therapy.

METHODS

This was a prospective, noninterventional study (registry) in neurological centres (hospitals and offices) throughout Germany.

RESULTS

As of 1 December 2015, 80 patients with MMN were included (mean age 55.4 ± 9.8 years, 67% males, mean disease duration 10.7 ± 10.2 years). The affected limb regions were predominantly distal muscle groups of the upper extremities. On the inflammatory neuropathy cause and treatment (INCAT) scale, 94% of the patients had some disability in the arms and 61% in the legs. At inclusion, 98.8% received IVIG and 1.3% SCIG. Substantial variation was observed between IVIG treatment intervals (every 0.7 to 17.3 weeks) and dosage (0.2-2.1 g/kg body weight received during a single administration; mean monthly dosage, 0.9 g/kg body weight). However, the mean monthly dosage was steady over time. At 1-year follow up, improvement was seen in muscle strength, INCAT and quality of life (QoL) scores (SF-36 questionnaire).

CONCLUSIONS

The management of patients with MMN in everyday clinical practice demonstrates a wide range of absolute dosages and treatment intervals of IG, supporting the recommended practice of determining treatment dose on an individual patient basis. The improvements in muscle strength and reduction in disability, accompanied by increased QoL, strengthen the case for use of IG as a maintenance treatment for MMN.

New Frontiers in Subcutaneous Immunoglobulin Treatment

Subcutaneous immunoglobulin (SCIG) treatment provides stable serum immunoglobulin G (IgG) levels, is associated with fewer systemic adverse events than intravenous immunoglobulin (IVIG) treatment, and offers the convenience of home therapy. In clinical practice, IVIG is still used preferentially for initiation of treatment in newly diagnosed patients with primary immunodeficiency (PI) and for immunomodulatory therapy, such as treatment of peripheral neuropathies, when high doses are believed to be necessary. The authors discuss recent experience in using SCIG in place of IVIG in these settings. SCIG has been successfully used for initiation of therapy in previously untreated PI patients. Seventeen of 18 PI patients achieved serum IgG levels ≥5 g/L after the loading phase. Daily treatment was well tolerated and provided opportunities for patient/parent training in self-infusion. SCIG has been used for maintenance therapy in multifocal motor neuropathy (MMN) in three recent clinical trials, with good efficacy and tolerability results. Seven of eight MMN patients maintained serum IgG levels of 14–22 g/L with a mean dose of 272 mg/kg/week, had stable muscle strength, and felt comfortable with self-administration. Four patients with polymyositis or dermatomyositis achieved improvement in serum creatine kinase levels and muscle strength with SCIG therapy. Recent experience with SCIG suggests that traditional concepts of immunoglobulin therapy may be challenged to increase available therapy options. SCIG can be used to achieve high IgG levels within several days in untreated PI patients and to maintain high serum levels, as shown in patients with MMN.