GRAd-COV2 vaccine provides potent and durable humoral and cellular immunity to SARS-CoV-2 in randomized placebo-controlled phase 2 trial

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and heterologous immunization approaches implemented worldwide for booster doses call for diversified vaccine portfolios. GRAd-COV2 is a gorilla adenovirus-based COVID-19 vaccine candidate encoding prefusion-stabilized spike. The safety and immunogenicity of GRAd-COV2 is evaluated in a dose- and regimen-finding phase 2 trial (COVITAR study, ClinicalTrials.gov: NCT04791423) whereby 917 eligible participants are randomized to receive a single intramuscular GRAd-COV2 administration followed by placebo, or two vaccine injections, or two doses of placebo, spaced over 3 weeks. Here, we report that GRAd-COV2 is well tolerated and induces robust immune responses after a single immunization; a second administration increases binding and neutralizing antibody titers. Potent, variant of concern (VOC) cross-reactive spike-specific T cell response peaks after the first dose and is characterized by high frequencies of CD8s. T cells maintain immediate effector functions and high proliferative potential over time. Thus, GRAd vector is a valuable platform for genetic vaccine development, especially when robust CD8 response is needed.

A case of melioidosis probably acquired by inhalation of dusts during a helicopter flight in a healthy traveler returning from Singapore

We present a case of melioidosis in an Italian male returning from Singapore after a short travel. He probably acquired the disease by inhalation, which is not the typical mode of transmission, in the absence of evident risk factors. The diagnosis was confirmed by real-time polymerase chain reaction of the culture while serology was useful to assess professional exposure among laboratory workers. Treatment consisted of an initial intensive phase with meropenem and trimethoprim-sulfamethaxazole (TMP-SMX), followed by 6 months of eradication therapy with TMP-SMX.

Lopinavir pharmacokinetic profiles in HIV-infected patients during rifabutin-based anti-mycobacterial therapy

OBJECTIVES

To evaluate the pharmacokinetic profile of ritonavir-boosted lopinavir in HIV-infected patients during rifabutin-based anti-mycobacterial therapy.

PATIENTS AND METHODS

A longitudinal, cross-over pharmacokinetic evaluation of lopinavir with and without rifabutin in HIV-infected subjects with mycobacterial disease was done. All received lopinavir/ritonavir (400/100 mg twice a day) + an adjusted rifabutin dose of 150 mg every other day. Twelve-hour lopinavir pharmacokinetic sampling occurred at 2 weeks (T1) and 6 weeks (T2) after starting combined therapy and 10 weeks after completion of adjusted rifabutin (T3). Plasma was assayed using an HPLC method; lopinavir plasma concentration-time data were analysed using non-compartmental methods.

RESULTS

In 10 patients with complete lopinavir curves at T1, T2 and T3 pharmacokinetic values were, respectively: AUC(0-12), 187.5, 161.8 and 121.1 μg · h/mL; C(trough), 13.2, 10.0 and 7.7 μg/mL; C(max), 18.7, 15.9 and 13.3 μg/mL; and apparent oral clearance (CL/F), 0.035, 0.037 and 0.045 L/h/kg. Lopinavir C(trough) and AUC(0-12) were significantly higher at T1 compared with T3 while CL/F remained unchanged throughout. Combined treatment was well tolerated and none of the patients experienced moderate to severe lopinavir-related adverse events.

CONCLUSIONS

Lopinavir serum concentrations are not reduced when the drug is administered together with an adjusted dose of 150 mg of rifabutin every other day.