Well-known criminal lawyer Ujjwal Nikam will be the Special Public Prosecutor in the case, Satara Superintendent of Police Sandip Patil said.
The high-profile case had created a sensation last August after Pol -- who earned the moniker of 'Dr Death' -- allegedly confessed to committing the murders.
Wai police station Senior Inspector Vinayak Vetal said the DNA sample reports of three of the six victims are positive, two have not been sent while nobody is available to match samples from an orphan Salma Sheikh.
"Samples of Mangala Jedh, Nathmal Bhandari and Jagabai Pol have tested positive at the Forensic Sciences Laboratory in Pune," Vetal told IANS.
Vetal has been looking into the case for the past five months.
Pol, 41, and Mandre, 25, have been accused of luring and killing at least six persons, including five women, with lethal injections, robbing them of their gold and later burying the bodies at the medico's big poultry farmhouse, about 13 km from picturesque Wai.
Vetal said police have filed three charge sheets so far against the two accused, presently in custody.
The remaining three charge sheets are expected to be submitted later this month. Regular court hearings in the cases are likely to start around February, he said.
The duo's victims included Surekha Kisan Chikane, killed on May 20, 2003; Vanita Narhari Gaikwad, killed on August 12, 2006; Jagabai Laxman Pol, killed on August 13, 2010; Nathmal Dhanaji Bhandari, killed on December 7, 2015; orphaned nurse Salma Shaikh, killed on January 17, 2016; and Mangal Jedhe, killed on June 16, 2016.
Forensic and chemical analysis of lethal injections used to kill the victims are awaited. Police said Pol stole these from Ghotawadekar Hospital in Wai where he was once employed as Intensive Care Unit incharge.
Wai police had raided the hospital run by medico Vidyadhar Ghotawadekar and seized several medical records and documents.
Several jewellers and traders from Wai and surrounding areas were questioned after Pol revealed he ran a ponzi scheme with the promise to double gold jewellery.
Pol was arrested from Mumbai on August 11 after police launched a probe into the mysterious disappearance of Mangal Jedhe, President of Maharashtra Purva Prathmik Shikshika Sevika Sangh, on June 16.
He confessed to the killing of six persons, revealed the role of his alleged accomplice Mandre, how they killed their victims and buried them at his farmhouse and planted saplings on the graves.
Said to be an 'electro-homoeopath', Pol practised at some Wai hospitals and at his farmhouse, around 175 km south of Mumbai, near the famous twin hill stations of Mahabaleshwar-Panchgani.