Use of an alfa-lipoic, Methylsulfonylmethane, Boswellia serrata and Bromelain dietary supplement (OPERA®) for aromatase inhibitors-related arthralgia management (AIA): a prospective phase II trial (NCT04161833)

Aromatase Inhibitors (AIs) are recommended for the adjuvant treatment of hormone receptor positive breast cancer in both high-risk pre-menopausal and post-menopausal population; arthralgia is the main cause of discontinuation of therapy and affects up to 25% of population on AI treatment. The objective of the study was to prospectively evaluate OPERA® (GAMFARMA srl, Milan, Italy), a new dietary supplement where α-Lipoic acid, Boswellia serrata, Methylsulfonylmethane and Bromelain are combined in a single hard-gelatin capsule to be taken once a day. Fifty-three patients with arthralgia (NCI-CTCAE v4.0 grade ≥ 1) occurring during AI therapy were enrolled. All patients received OPERA® from enrollment (T0) up to sixth months (T3). Patients' AI-related arthralgia was evaluated every two months with VAS Scale, PRAI questionnaire, and CTCAE scale. Primary endpoint was the number of patients with symptom resolution (G0) at T3 if compared to T0, according to CTCAE and VAS scale. Secondary endpoints were decrease in arthralgia intensity measured with PRAI score at T3 compared to baseline, safety of OPERA® and rate of AI interruption. Treatment with OPERA® supplement was overall well tolerated; no relevant toxicities related to OPERA® intake were reported. Seven subjects (13.2%) were not included in the final analysis because of consent withdrawal. 46 participants were eligible for final analysis. According to CTCAE scale, 10 out of 46 patients reported symptoms resolution at 6-month follow-up from the time of enrollment T0 (p = 0.0009). According to VAS score, 5 patients reported complete resolution of symptoms at T3 if compared to baseline starting situation T0 (p = 0.0222). Analysis of PRAI score showed a significant reduction in arthralgia-related pain perceived (p = 0.0001). OPERA® was able to reduce the intensity of arthralgia related to AI therapy. Randomized, double-blind studies are warranted to confirm the effectiveness of this dietary supplement.


Introduction
Aromatase Inhibitors (AIs) are recommended for the adjuvant treatment of hormone estrogen receptor positive (ER+) breast cancer (BC) in the post-menopausal population and in high-risk pre-menopausal patients in association with LHRH analogues. Third generation aromatase inhibitors have been shown to significantly improve patients' outcome [1][2][3]. Along with their wellknown detrimental effect on bone-health, one of the most peculiar AI-related side effects is represented by arthralgia [4]. Arthralgia affects up to 25% of patients on AIs, inducing AI suspension in a significant proportion of patients [5]. As non-compliance and early discontinuation of the treatment leads to a poorer prognosis [3], this raised growing interest in its management. Treatment of arthralgia is generally based on the use of pharmacological, non-pharmacological, and complementary medicine intervention. Commonly used drugs comprise nonsteroidal anti-inflammatory drugs (NSAIDS), anticonvulsants, neuroleptics, and antidepressants (among which duloxetine plays an emerging role with best evidence in the management of AI-related arthralgia so far) [6][7][8]24]. However, long term use of these medical aids is often associated with important side effects [9]. Alternatively, physical therapy intervention and acupuncture have shown some benefit [10][11][12].
OPERA® (GAMFARMA srl, Milan, Italy) is a new dietary supplement with a series of compound with a theoretical impact on osteoarthritis and inflammatory conditions.
To evaluate the efficacy of OPERA® for AI-related arthralgia management, a phase II, monocenter, self-controlled clinical trial was designed and carried out in our institution.

Methods
ER + early BC post-menopausal patients, 18 years or older, with a Karnofsky performance status (KPS) ≥ 70, reporting arthralgia of any grade (≥ G1) during adjuvant AI therapy were included in this phase II, monocenter, self-controlled prospective trial.
OPERA®, as mentioned above, is a new dietary supplement with a series of compound with a theoretical impact on osteoarthritis and inflammatory conditions [α-Lipoic acid (240 mg), Boswellia serrata (BS) (40 mg), Methylsulfonylmethane (MSM) (200 mg), and Bromelain (20 mg)] combined in a single hard-gelatin capsule.
The role of alpha lipoic acid lies in its antioxidant activity capable of neutralizing both oxidative reactions and reducing the resulting oxidized forms, the latter involved in the onset and worsening of pain. Boswellic acids hinder the action of an enzyme (such as 5-lipoxygenase and elastase) responsible to produce substances that facilitate inflammatory processes. Methylsulfonylmethane has a chondroprotective activity by stimulating the synthesis of articular cartilage. Bromelain is an anti-edema proteolytic enzyme. All these compounds are particularly effective in the treatment of localized inflammation of the soft tissues and are useful in the treatment of pain and inflammation of various tissues and in osteoarticular pain deriving from osteoarthritis and degenerative and inflammatory processes of cartilage.
OPERA® is made according to GMP EU "Good Manufacturing Practice Europee", it was subjected to regular chemical-pharmaceutical controls and registered and notified to the Italian Ministry of Health.
All patients were required to take orally OPERA® one capsule of 12 mg once daily, preferably in the morning on an empty stomach as first line treatment in the management of AI-related arthralgia. Patients were required to continue their AI throughout the 6 months period and thereafter if tolerated. Patients were not allowed to take other medications or supplements to relieve their joint pain during this time. Physical activity was not contraindicated, but we did not report if it was regularly practiced.
Arthralgia was assessed at the enrollment visit and subsequently every two months up to the sixth month after enrollment, using the following items: 16-item Patient-Reported Arthralgia Inventory (PRAI) [5], Italian version, Visual Analog pain Scale (VAS) [14] and NCI-CTCAE v4.04 [13]. Overall, clinical assessment was performed at baseline (T0) and at 2, 4, and 6 months (T1, T2, and T3, respectively). There are no known side effects for the use of the OPERA food supplement; therefore, we reported any disturbance that could be treatment-related and defined them according to NCI-CTCAE v4.0.
Primary endpoint was symptom resolution at T3 if compared to T0, measured with CTCAE and VAS scale.
Secondary endpoints were decrease in arthralgia intensity measured with PRAI score at T3 compared to baseline, safety of OPERA® and rate of AI interruption. Informed consent was obtained from all individual participants included in the study. Study design procedures were reviewed and approved by the local institutional ethics committee. Information about this phase II trial is available in the National Institute of Health site at http:// www. clini caltr ials. gov (NCT04161833). Continuous variables were presented with descriptive statistics. The 95% confidence interval of the arithmetic median or of the percentage frequency were calculated for the variables of clinical-prognostic interest.
Interruptions of treatment were calculated as a percentage. Only patients receiving complete follow-up (6 months of treatment) have been considered in the final analysis. All data were statistically analyzed using MedCalc Statistical Software version 18.2.1 (MedCalc Software bvba, Ostend, Belgium; http:// www. medca lc. org; 2018). Chi square test was used to test the difference in terms of arthralgia prevalence measured by CTCAE and VAS scale at baseline and last follow-up, after 6 months. Variations in terms of median PRAI score at 6 months were tested through Wilcoxon test. To detect a statistically significant decrease of arthralgia (standard 20% decrease assumed) with symptoms resolution at T3 if compared to baseline, a sample size of 46 was needed with a statistical power of 80% and a significance level of 0.05. Considering a dropout rate of 10%, 51 enrolled patients represented the final sample size.

Results
Between November 2018 and April 2019, 53 patients were recruited (Fig. 1). All patients provided written informed consent. Mean age was 59 years (43-82), presenting mostly with KPS 100 (75% of cases). Twenty-five patients (45.3%) previously received chemotherapy in either neoadjuvant or adjuvant settings. The 94.33% of these patients received a taxane-based regimen in combination either with anthracyclines and/or trastuzumab. No patients reported neuropathy at the end of chemotherapy according to CTCAE. Concerning adjuvant hormonal therapy, letrozole was prescribed in most cases (48 patients, 90.5%). Full patients and treatment characteristics are listed in Table 1. Arthralgia occurred within a mean time of 21 months since the start of AI treatment (range 2-52 months).
Seven subjects (13.2%) decided to end their participation in the study prematurely after the enrollment and withdrew their consent for personal reasons. Therefore, they were excluded from analysis, as it was not possible to analyze the PROMs related to this subset patients. Forty-six participants were eligible for final analysis. Treatment with OPERA® supplement was overall well tolerated by patients. No significant acute toxicity related to the intake of OPERA® was reported during the study period; only two patients (4.35%) reported a G1 gastralgia, with no discontinuation of tablets. After 24 weeks of OPERA® administration, a significant improvement in arthralgia was detected. G2 arthralgia according to CTCAE scale is clinically meaningful (moderate pain, instrumental ADL limitations) compared to G1 (light pain). According to CTCAE scale, at baseline T0, most patients had G1 (43%) and G2 arthralgia (54%) with one patient presenting with G3 arthralgia (2%). At 6-month follow-up T3, a significant reduction in G ≥ 1 arthralgia assessed with CTCAE (Fig. 2) was observed, with 57% presenting with G1 symptoms, 17% with G2 arthralgia and with 10 out of 46 patients (22%) reporting symptoms resolution if compared to T0 (p = 0.0009). According to VAS (Fig. 3), at T0 54% of population was categorized as VAS2, 37% Analysed (n= 46) Excluded from analysis (n=7) Analysis 7 patients refused to continue the study and withdrew their consent for personal reasons. Follow-up was available for 46 patients, then included in the final analysis..

Enrollment
Assessed for eligibility (n= 53)  (Fig. 4). Compliance to AI therapy was assessed during every scheduled visit and resulted in a 100% adherence at the time of study completion. No disease recurrence was reported at the end of study follow-up.

Discussion
Oncological outcomes have been radically improved in recent years and the important achievements obtained in BC field have led to a growing interest in long term side effects of any pharmaceutical intervention prescribed in this setting, especially in the context of ER + BC, which represents the most common type of BC diagnosed [15]. Nowadays, AI hormonal therapy is the cornerstone for the adjuvant treatment of ER + early breast cancer [1][2][3]. However, AI-related increase in musculoskeletal symptoms was reported in all major trials leading to their approval [5,16,17]. The set of disorders and musculoskeletal symptoms reported by patients on AI therapy is commonly defined as arthralgia, to distinguish the series of discomforts, unrelated to degenerative or inflammatory pathologies, from arthrosis or arthritis. The clinical presentation and the severity of the symptoms are quite variable; generally, the manifestation is symmetrical and bilateral, involving small joints; mainly it manifests itself upon awakening, inducing motility reduction and begins within two months from treatment start. However, a late presentation is not uncommon, even two

NCI-CTCAE arthralgia
years after the start of treatment [18]. Moreover, in some cases symptoms may become increasingly severe, representing a significant limitation for normal daily activities and finally leading to treatment discontinuation. Despite the high incidence rate, little is known about the etiopathogenesis of these symptoms; the low estrogenic levels could represent the triggering cause [19]. Several pharmacological and nonpharmacological methods aimed at reducing arthralgia and improving therapy adherence with AIs have been analyzed in recent years. Arthralgia is commonly treated using NSAIDs, paracetamol, and other analgesic drugs. However, no highlevel evidence supports the use of these treatments, aside from some published cross-sectional surveys [20,21]. Alternatively, a switch to another AI has been investigated in prospective trials [22]. In their study, Briot et al. switched 179 patients who had discontinued anastrozole due to arthralgia to letrozole after a one-month wash-out period. Improvement in arthralgia and in extended compliance to AI medication beyond 6 months was reported. Concerning other pharmacological interventions, Prednisolone have been tested with promising results in small patient cohorts [23]. Duloxetine, indeed, was also tested in a large, randomized phase III trial (SWOGS1202) by Henry et al. [24]. Treatment population, as in our experience, included 299 stage I-III post-menopausal patients in adjuvant endocrine therapy with AIs for early BC and was randomized in a 1:1 fashion to duloxetine or placebo for 13 weeks for treatment of muscular-skeletal symptoms. Primary endpoint was average joint pain through 12 weeks and in the results duloxetine proved superior to placebo in the management of AIMSS although related to more frequent low-grade toxicities. Based on this study, Henry and colleagues then analyzed the association between Body Mass Index (BMI) and response to Duloxetine in patients with AIMSS, showing that obese patients obtained more benefit from duloxetine [25]. Concerning non-pharmacological interventions, yoga and exercise have been tested in a series of retrospective and prospective experiences with favorable results; nonetheless small patient number and non-validated outcome measures were common in these published experiences [12,26,27]. Acupuncture has been tested in randomized clinical trials (RCTs) with mixed results, with only one trial showing a benefit of acupuncture versus sham procedure in arthralgia reduction [12,[28][29][30][31][32]. Among nutraceuticals, omega-3 fatty acids (O3-FAs) have been investigated due to their known beneficial effect in rheumatoid arthritis. In a study conducted by Hershman et al., 262 women were randomly assigned to receive either O3-FAs or placebo for 24 weeks. Compared with baseline, the mean observed Brief Pain Inventory-Short Form (BPI-SF) score decreased by 1.74 points at 12 weeks and 2.22 points at 24 weeks with O3-FAs and by 1.49 and 1.81 points, respectively, with placebo [33]. The authors concluded that no meaningful difference was appreciable between O3-FAs and placebo arm in terms of arthralgia reduction.
Other nutraceuticals have also been tested in this setting. Notably, a single-arm study assessed the efficacy of a complementary medicine regime involving sodium selenite, lens culinaris lectin, and plant enzymes including Bromelain. One-hundredtwenty-nine patients receiving either tamoxifen or AIs were enrolled in this trial. Benefit with this regime evaluated with an unvalidated PROM was reported by the authors [34]. Our study represents one of the few prospective trials demonstrating significant benefit in terms of arthralgia resolution with validated objective and PROMs assessment in a single cohort of patients undergoing AIs adjuvant therapy. Of course, several limits should be acknowledged when referring to our study. In fact, limited sample size and heterogeneity of included patients could have influenced the results. Patients' mean age was 59 years while incidence of arthralgia is higher in older patients. We included only early BC post-menopausal patients without regarding high-risk pre-menopausal population.
Taxanes are notably associated with independent increase of the risk of developing joint pain [35][36][37]. In our study population we did not evaluate the impact of taxanes on arthralgia and on its management. In other experiences reported in literature, taxanes are significant predictors of pain and of low baseline quality of life, in addition to AIs [38,39]. In Crew et al. experience [40] patients who received taxane chemotherapy were more than four times likely than other patients to have AI-related joint pain and stiffness. Also, in Beckwee's work [41] one of the predictors for the development of AIA included taxane-based chemotherapy.
On the other hand, some studies report contrasting results about the impact of a taxane-based regimen on the development of AIA. According to Kellogg Cancer Center work, there is no statistical difference in the incidence of arthralgias in patients under AI treatment with a history of chemotherapy (including taxane therapy) compared to those who did not receive chemotherapy [42]. In the Chinese experience [43], taxane use is not associated with arthritis or carpal tunnel syndrome compared to other chemotherapy regimens. Also, Italian experience shows no difference in the incidence of arthralgia in patients on AIs who had received taxanes or anthracyclines [44].
Furthermore, it has not been assessed whether the reduction in pain symptoms was also associated with a significant improvement in terms of quality of life. Overall, OPERA® administration in symptomatic patients yielded a significant reduction in rate and severity of reported pain and osteoarticular symptoms according to CTCAE [13] and VAS [14], with a significant decrease in symptoms severity according to the PRAI scale.
One of the main reasons for scarce adherence to AI therapy is the onset of side effects like musculoskeletal symptoms. The assumption of OPERA® may represent a significant advantage in compliance to AIs, therefore leading to a more effective hormone therapy with subsequent better outcomes in disease control. The treatment was overall well tolerated, with no significant side effects. These findings further corroborate the promising results reported by our group in a previous experience, where OPERA® intake was shown to improve chemotherapy-induced peripheral neuropathy (CIPN) symptoms in a series of prospective patients previously exposed to neurotoxic chemotherapy [45].

Conclusion
In conclusion, our findings about OPERA® daily intake show promising results in the management of AI-induced arthralgia in the setting of post-menopausal patients. Randomized double-blind studies are warranted to confirm the effectiveness of this dietary supplement. Furthermore, it is necessary to investigate the impact of arthralgia reduction in terms of quality of life and compliance with AI treatment.